
Class_ 

Book 

Copyright N? 






COPYRIGHT DEPOSIT. 



LABORATORY MANUAL 



TO ACCOMPANY 



SMALLWOOD, REVELEY, AND BAILEY'S 



BIOLOGY FOR HIGH SCHOOLS 



BY 

GUY A. BAILEY 

AND 

ROBERT A. GREEN 

GENESEO STATE NORMAL SCHOOL 
GENESEO, NEW YORK 



^x>:*sc 



> > • 



ALLYN and BACON 

BOSTON NEW YORK CHICAGO 

ATLANTA SAN FRANCISCO 






v 



COPYRIGHT, 1922 

BY GUY A. BAILEY 

AND ROBERT A. GREEN 



Nortooofc prras 

J. S. Cushing Co. — Berwick A Smith Co. 

Norwood, Mass., U.S.A. 



MAR 15 1922 
g)C!.A6549;jl 



•w* / 



"The invariable adaptation of an animal to the life it leads is one 
of nature's most instructive lessons, and can be discovered and appre- 
ciated by every pupil, but never through oral teaching or from reading 
of books. Better a child should learn to handle one animal, to see 
and know its structure and how it lives and moves, than to go through 
the whole animal kingdom with the best text-book under the best 
teacher, aided by the best charts ever made. The former would have 
learned what real knowledge is and how to get it, while the latter would 
have simply learned how to pass at his school examination." 

— Alpheus Hyatt. 



PREFACE 

This manual is intended to bring to the pupil's attention 
the adaptations of plants and animals to the place they 
hold in the organic world. We do not intend to substitute 
laboratory work for class room work, but to reenforce the 
work of the class room with a study of the actual forms in 
the laboratory or in the field. 

Whatever may be the ideal method of teaching biology 
from a theoretical point of view, practical school men know 
that biology must be fitted into a crowded curriculum and 
that often certain adjustments must be made that are not 
in keeping with the most approved methods. This book 
has been written with the realization that pupils have other 
classes to attend and that in many schools consecutive 
laboratory periods are not practical. 

To equip a modern biology laboratory with all the desirable 
biologic aids called for in any text-book is beyond the means 
of the average high school. So we have endeavored to make 
use of those aids most easily and economically available. 

For schools which have not enough compound microscopes 
to accommodate each pupil we have directed attention, as 
a substitute, to lantern slides made from actual photographs 
of the subject. Where these slides are not obtainable the 
laboratory study of accurate charts is recommended. 

The use of the microscope is a highly technical problem. 
Too often the pupil's time is consumed in looking for the 
thing rather than in looking at it. The use of slides and 
charts enables the teacher to call attention to the important 



vi PREFACE 

thing to be emphasized and much valuable timo may be 
saved. 

We have aimed to cover all the work required by the 
average syllabus of biology and yet to keep away from what 
seems too technical without omitting important and sig- 
nificant topics. 

Adaptation has been the dominant word in the minds of 
the authors, and structure has been treated to show adapta- 
tion. Without trying to convey the idea that there is a 
reason for everything or that if the human mind were pene- 
trating enough it could find a use for everything, we have 
tried to direct the pupil to inquire how structures are adapted 
so as to enable the animal to survive in the pitiless struggle 

for existence. 

G. A. B. 

R. A. G. 

February, 1922 



CONTENTS 

PAGE 

Introduction 1 

ANIMAL BIOLOGY 

The Grasshopper ......... 3 

The Cabbage Butterfly ........ 8 

The Egg — The Larva — The Pupa — The Adult. 

The Honey-bee 13 

The House-fly 15 

The Mosquito 17 

The Egg — The Larva — The Pupa — The Adult. 

The Beetle .......... 20 

General Study of Insects .22 

The Crayfish 23 

Dissection of the Crayfish. 

The Fish 29 

The Frog 33 

Dissection of a Frog. 
Mounted Bird .......... 38 

Field Trip to Study Birds 40 

Report Forms. 

Mammals ♦ 43 

The Paramecium 45 

Reaction to Stimuli — Food-taking — Execretion — Cell 
Structure. 

The Sponge 49 

Hydra 51 

The Earthworm 54 

Dissection of the Earthworm. 

The Starfish 59 

Fresh-water Clam 62 

vii 



Vlll CONTENTS 



INTERRELATIONS OF PLANTS AND ANIMALS 

PAGE 

The Balanced Aquarium 6 1 

The Hay Infusion 66 



PLANT BIOLOGY 

Flowers 68 

Parts of a Flower. 

The Composite Family 70 

The Dandelion. 

Insect-pollinated Flowers 73 

Study of Wind Pollination 75 

Wind-pollinated Flowers 77 

The Oak, a Monoecious Form. 

Seeds and Fruits 79 

Castor Bean — Dent Corn. 

Study of Germination 

Tests for Foodstuffs in Seeds and Fruits .... 84 
Test for Grape Sugar — Test for Starch — Test for Protein — 
Test for Oil. 

To Test Seeds for Germinating Qualities .... 87 
Corn Test. 

Test for Viability of Seeds s^> 

To Study Conditions Necessary for Germination . . s '' 

Moisture — Temperature — Oxygen — To Test Germinating 
Seeds for C0 2 . 

Roots 92 

The Carrot — The Onion Root — Wheat Kernels — Corn — 
Fibrous Roots — Fascicled Roots — Aerial Roots. 

Stems . 

The Horse-chestnut Stem — Cross-sect ion of a Woody Sinn — 
Stems in Their Relation to Life — Sunflower Stem — ( torn Stem. 

Modified Stems . 102 

The Potato — The Onion — The Cabbage — Other Sterna. 



CONTENTS 



IX 







PAGE 




. 105 


General Characters — The Maple Leaf — Leaf Forms - 


- Func- 


tions of Leaves. 








Adaptations of Plants That Serve as Protection 






Algae, for Example, Spirogyra 




. 118 


Bacteria 




. 119 


Fungus, for Example, Bread Mold 




. 121 






. 122 


The Lower Plants 




. 124 


The Fern. 







HUMAN BIOLOGY 

Adaptation of the Human Hand 126 

The Head 127 

The Backbone 128 

The Feet 129 

Digestion 130 

Mouth Digestion — Stomach Digestion — Intestinal Digestion 
— Action of Bile. 

Osmosis 133 

The Teeth . . . . « 134 

Bones 135 

Skin 136 

Nerve Tissue 137 

The Eye 139 

The Ear 140 

The Cell 141 



INTRODUCTION 

Biology in the high school is a newer expression than 
zoology or botany or human physiology. These subjects 
were formerly treated in ten or thirteen weeks, and too 
often were considered as separate and unrelated subjects. 
As a matter of fact they are all intimately related, and it 
is the appreciation of this relationship that gives the great- 
est value to the newer term, biology. 

Botany, plant study, taken with zoology, animal study, 
and both kept in mind as we consider man in his material 
surroundings, gives us an idea of biology. Human phys- 
iology alone is hardly what we mean, for we turn our atten- 
tion to man's adaptation to the life he leads. We consider 
sanitation and the cause and prevention of disease. These 
hardly belong to human physiology. 

Whether it is man, the highest type of animal, or the 
amoeba of the lowest group, or whether it is the big tree or 
the lowly moss, there are terms to which all may be re- 
duced. The first of these common terms is motion, for 
in some way or other there is motion of some form in all 
kinds of living things. A second common term is nu- 
trition, for food in some form and in some way must be sup- 
plied to all living things. A third common term is res- 
piration, for all forms seem to require oxygen in order to 
live and derive energy. A fourth term is excretion, for 
all organic forms give us waste products either in gaseous 
form or liquid or solid. In some plants the waste is held 
as crystals in the tissues. A fifth common term is sensa- 

1 



2 INTRODUCTION 

Hon. All animals and plants have a way of responding to 
some exciting causes (stimuli) to a greater or lesser degr< 
Lastly there is the common term of reproduction, whereby 
forms of life reproduce their kinds, and thus make good, in 
a measure, the inroads of disease, accident, and violence 
on their numbers. 

So we have six common terms to be sought for in every 
animal or plant that lives or has ever lived. The labora- 
tory enables us to see many of these terms as they arc 
worked out on the table. We may see how a plant giv< 
off a waste, carbonic acid gas. We may see how an amoeba 
takes in food (a part of nutrition). The flower when re- 
duced to these terms becomes a device for the production 
of seeds (reproduction). A kernel of wheat may be food 
for man, but in our scheme of common terms it becomes an 
agent of reproduction for the wheat plant . 

The geranium turns its leaves towards the window, and 
this is an example of sensation. So we mi<2;ht go over the 
whole list of plants and animals and inquire for each of 
the common terms. The laboratory gives us the oppor- 
tunity to start the investigation, and then the whole wide 
world may become our laboratory in which to inquire ae 
long as we live. 



ANIMAL BIOLOGY 

THE GRASSHOPPER 

Take a field trip into a pasture or a field and secure as 
many grasshoppers of all sizes as possible. Each student 
should have a large adult specimen which has been pre- 
served in formaldehyde, and a wire cage containing sods 
should receive the living grasshoppers. This should be 
placed where it may be observed by the class as they study 
this animal. 

Examine the preserved specimen closely. 

1. How long is your specimen? 

2. What is its color? 

3. Describe the place where it was found. 

4. How is it protectively colored? 

5. What kind of skeleton does the grasshopper possess? 

6. Can you see any advantage in this ? 

7. How many distinct regions of the body can you find? Name 
them. 

8. What is the shape of the head? Is it movable? 

9. Is there a neck? 



4 ANIMAL BIOLOGY 

10. How many large eyes do you find? 

11. Examine one under a hand lens or compound microscope. 
Is it made up of one or many parts? Such eyes are said to be com-| 
pound. 

12. The grasshopper also has three small eyes which are simple 
(not compound). One is located in the middle of the forehead and 
one near each compound eye. Describe what you can see of one. 

13. Locate them with reference to the compound eyes. 

14. How many antennae does the insect have? 

15. Compare their length with the body length of the specimen. 

16. Are they movable? Explain. 

17. How many distinct mouth-parts are there? 

18. The upper lip is called the labrum. Describe it as to shape 
and size. Is it movable? See text for other mouth-parts. 

19. The jaws are called mandibles. How do they work? 

20. What is the food of the grasshopper? 

21. How are the mouth-parts specially adapted for this kind of food? 

22. Show exactly what happens when a grasshopper feeds. 



THE GRASSHOPPER 5 

23. Make a drawing (X5, that is, five times the natural size) of the 
head as seen from the front, and label compound eyes, simple eyes, 
antennae, labrum, and mandibles. 



24. The thorax is divided into three parts, the pro-thorax (front), 
the meso-thorax (middle), and the meta-thorax (back). Their bound- 
aries are not always clear. Try to distinguish them. 

25. How many appendages for locomotion can you find? 

26. To which part of the thorax is each appendage attached? 

27. How many pairs of wings are there? 

28. How are they carried when the grasshopper is resting? 

29. Which pair is most useful in flying? 

30. What function does the smaller pair perform? 

31. Describe each pair as to size, shape, and texture. 



32. How many legs has the insect? 

33. Which legs are used most for walking? 

34. How are they adapted for this use? 

35. After watching a live grasshopper, explain carefully how it walks. 



6 AN I MAI BIOLOGY 

36. What legs are used for jumping? How are they fitted for this 
function ? 

37. Examine the jumping leg closely. Of how many parts is it com- 
posed ? 

38. The part nearest the body is called the trochanter; the long 
muscular part, the femur; the slender spiny part, the tibia; and 
the three sections of the foot, the tarsus. 

39. Describe each part as to relative size, shape, color, and special 
adaptations which fit it to perform its special function. 



40. Explain just exactly how the grasshopper jumps. 

41. 'Make a drawing (X3) of the jumping leg of the grasshopper, 
labeling all parts. 



42. How many segments in the abdomen? 

43. Most of the spiracles or breathing pores are located in the 
ments on each side of the abdomen. How many spiraclefl do you find 
in each segment ? 

# 

44. What is the depression and membrane in the first abdominal 
segment ? 



THE GRASSHOPPER 7 

45. Watch closely the abdomen of a living grasshopper. Describe 
any movements you may observe. 

46. The female may be distinguished by a pair of blunt spines called 
the ovipositor at the tip of the abdomen. Determine the sex of your 
specimen. 

47. For what purpose does the female use the ovipositor? 

48. In what ways does the nymph (immature form) differ from the 
adult? 

49. What kind of metamorphosis does the grasshopper illustrate? 

50. Of what economic importance is this insect? 

51. Name some of the other common members of this same family. 

52. Write a complete life history of the grasshopper. 



53. Make a drawing (X5) of the entire grasshopper, labeling all 
parts. 



THE CABBAGE BUTTERFLY 
(Pieris Rapae) 

Stages of Development 

A visit to a cabbage patch will usually provide the class 
with a wealth of material. Secure cabbage leaves with 
eggs on them and as many cabbage " worms" of all sizes 
as possible. Possibly you may find pupae hanging to the 
leaves. Put the cabbage leaves and specimens into a wire 
cage where they may be frequently observed. Feed the 
larvae fresh cabbage leaves daily. 

The Egg 

Examine the eggs of the cabbage butterfly without it - 
moving them from the leaf. 

1. Describe an egg as to size, shape, and color. 

2. On which surface of the leaf are the eggs commonly deposited? 

3. Are they deposited singly or in a cluster? 

4. How are the eggs protected? 

5. Make a drawing (X5) showing a few eggs attached to a cab- 
bage leaf. 

These eggs will hatch later, or larvae secured from the field may be 
observed. 



S 



THE CABBAGE BUTTERFLY 9 

The Larva 

6. Are the larvae ("worms") all the same size? Why? 

7. How many distinct body regions can you see? 

8. How many segments in your specimen? 

9. Can you see any evidence of spiracles? 

10. How many pairs of legs has the larva? 

11. Where are they located? 

12. What is the food of the larva? 

13. Observe it eating. For what kind of work is its mouth fitted? 

14. Make a labeled drawing (X2) of the larva. 



15. Can you find any larva wagging its head from side to side spinning 
a tangle of silk? It is preparing to change its form. 

The Pupa 

If the larvae are left in a warm, well-lighted room and fed 
fresh cabbage leaves every day, they will soon molt and 
pupate. 

16. If you have found a chrysalis in the garden, describe the exact 
place where you found it. If the caged larvae have pupated, in what 
part of the cage do you find the pupal cases? 



10 ANIMAl BIOLOGY 

17. Describe the chrysalis as to size, color, and texture. 



18. How is it held in place? 

19. How is it protected ? 



20. Make a drawing (X2) to show the shape and means of attachment 
of a chrysalis. 



Each student should have a preserved specimen, and there 
should be several living butterflies caged where they may be 
observed by the class. Examine a cabbage butterfly closely. 

1. Measure the body length of your specimen. 

2. How does it compare with that of the grasshopper? 

3. Into how many parts is the body divided? Name them. 

4. How many eyes can you find ? 

5. Are they simple or compound? 

6. Describe an antenna as to length and flexibility. 



7. What structure do you find at the end of the antenna? This 
is peculiar to butterflies; moths never have it. 



THE CABBAGE BUTTERFLY 11 

8. Spread them apart and disclose the mouth-parts. The two 
jaws or mandibles are long and fit together to form a tube called the 
proboscis. 

9. Measure its length. How does the butterfly carry the proboscis? 

10. What is the food of the butterfly? 

11. How is the proboscis especially adapted to secure this kind of 
food? 

12. If you have a living butterfly place it near some sweetened water 
or honey and describe the way it feeds. 

13. How many pairs of wings does the butterfly have? 

14. To what body region are they attached? 

15. What is the main color of the wings ? Are there other marking 
colors? 

16. Is the animal protectively colored? Explain. 

17. The female has two or more black spots besides the tip on each 
fore-wing, the male but one. Determine the sex of your specimen. 

18. Which pair of wings is the larger? 

19. What are the uses of the veins which you see in the wings? 

20. How are the wings carried when the butterfly is not flying? 



21. Observe a wing with a hand lens or compound microscope. 
With what is it covered ? 



12 ANIMAL BIOLOGY 

22. What evidences can you see of the way in which the butterfly 
breathes ? 

23. Make a drawing (X 3) of the cabbage butterfly, labeling eyes, 
proboscis, antennae, wings, legs, and abdominal segments. 



THE HONEY-BEE 

Each student should be provided with a preserved specimen 
of the worker bee. If possible have an observation hive with 
glass sides in the schoolroom ; if not, ask some bee keeper 
in the vicinity to show the class the bees in a movable frame 
hive. 

1. The body of the honey-bee is divided into how many sections? 

2. How does the body-covering of the bee compare with that of the 
grasshopper ? 

3. Compare the antennae of the bee and the grasshopper as to 
length and shape. 

4. Describe the compound eyes as to number and position. 

5. Use a hand lens and describe the simple eyes in number and po- 
sition. 

6. Note that the mouth-parts are composed of a couple of crude 
jaws and a long proboscis containing a hairy tongue. How long is the 
proboscis ? 

7. For what type of food do these parts seem fitted ? 

8. What is the natural food of the honey-bee? 

9. Where is this food found? 

10. How is the bee's mouth specially adapted for securing this food? 

11. How many legs do you find? On what region are they borne ? 

13 



14 ANIMAL BIOLOGY 

12. How are they adapted for the bee's special purpose? 

13. The blade part of the hind leg is called the scraper, What d 
it scrape? 

14. Make a drawing of the hind leg (X 4) of the bee, showing the 
scraper with ball of pollen attached. 



15. Examine the wings. To what region are they attached? 

16. Compare the front with the hind wings. 

17. How many segments are in the abdomen? 

18. How does the bee respire? 

19. The stinger is located at the tip of the abdomen. Describe it as 
to size and function. 

20. What kind of metamorphosis does the honey-bee illustrate? 

21. Write a life history of a worker bee. 



22. Of what economic importance are these insects to man? 

23. Draw a lateral view of the honey-bee (X 5), labeling all parts. 



THE HOUSE-FLY 

Each student should have a preserved specimen of the 
animal. If some raw meat be placed where flies may reach 
it, it will, in the course of a few days, furnish materials for the 
study of the fly development. 

Study your specimen carefully. 

1. Describe the fly as to size and color. 

2. Into how many regions is the body divided? Name them. 

3. How many compound eyes can you find? 

4. Examine one with a hand lens or compound microscope and 
make a drawing to show the shape and arrangement of the parts of the 
eye. 



5. Describe the proboscis as to size, shape, length, and color. 

6. What is the food of the house-fly? 

7. Where is the proboscis when the fly is not eating? 

8 To what part of the body are the legs and wings attached ? 
9. How many true wings does the fly have? 

15 



16 ANIMAL BIOLOGY 

10. Compare the position of the wings when at rest with the flying 
position. 

11. Look back of each wing for small membranes called ringlets. 
Are they separate or connected with the wings? 

12. The knobbed stalks back of the wings are called balancers. How 
many are there? 

13. How many legs has the fly? 

14. Are they all of the same length? 

15. Is the abdomen segmented? 

16. Describe the surface of the thorax and abdomen. 

17. Is the house-fly a friend or an enemy to man ? 

18. How may a fly spread disease? 

19. What methods may be employed to exterminate the. 

20. Name any other flies you may know. Are they harmful or bene- 
ficial? 

21. After examining a piece of flesh which has boon "blown" by Bkfl 
and contains "maggots," write a complete life history <>f the house-fly. 



22. Make a complete drawing (X5) of the side view of the house- 
fly, labeling all parts. 



THE MOSQUITO 

The class should make an excursion to a low, swampy 
region known to be infested with culex mosquitoes. Secure 
floating egg-masses if possible and a good number of " wig- 
glers" and keep them in the schoolroom in jars of the same 
water in which they were found living. If adults are to be 
kept for any length of time, small pieces of banana should 
be put in the jars with them. 

The Egg 

1. If you are fortunate enough to find the floating egg mass of the 
mosquito, observe the arrangement of the eggs. 

2. Can you make the egg mass sink? 

3. About how many eggs are there in the mass? 

4. Usually the eggs will hatch in from twelve to twenty-four hours 
after they are laid. From which end of the egg will the larva emerge ? 

5. Draw the egg mass (X10). 



The Larva 

6. How does the larva or "wiggler" move about? 

7. How does it breathe? 

8. Can you find any special organ for breathing? 

17 



18 ANIMAL BIOLOGY 

9. Can the larvae see? Support your answer. 



10. Near the head are bunches of hair which sweep currents of w 
containing food to the animal's mouth. How many such tufts can you 
see? 



11. How many antennae can you distinguish? 

12. Make a labeled drawing of the larva (X5). 



The Pupa 

13. After a few days the animal passes into its pupal stage. How 
has the shape changed? 

14. Is the pupa as active as the larva? 

15. Try to determine the number of body regions. 

16. The two hornlike projections are breathing tube-. How arc 
they used ? 

17. The pupa does not eat. Can you see any traces of legs or wingB ? 

18. Make a drawing of the pupa (X 5). 



The Adult 

After being in the pupal stage two or three days, the 
mosquito again changes its form. Try to observe this trans- 



THE MOSQUITO 19 

formation from pupa to adult. Adult specimens should be 
killed and provided for each student. 

19. How many body regions does the mosquito have? 

20. Male mosquitoes have long, bushy antennae, females short ones 
with few hairs. Determine the sex of your specimen. 

21. What is the natural food of the mosquito? 

22. How are the mouth-parts adapted for securing this food? 

23. How many wings does the mosquito have? 

24. How many legs ? 

25. Of what importance are mosquitoes to man? 

26. Where are mosquitoes most commonly found? 

27. How may they be kept under control ? 

28. Write a complete life history of the mosquito. 



29. Make a drawing of the left side of the mosquito (X 5), labeling 
all parts. 



THE BEETLE 

May beetles, or " June bugs/' as they are sometimes called, 
are perhaps the best beetles to study on account of their frize. 
If these are not obtainable, the potato beetle ("bug") or 
any of the many beetles commonly found on goldenrod and 
milkweed in the summer and autumn may be used. Each 
student should have a preserved specimen, and a few live 
ones should be kept and observed by the class. If possible 
secure some of the larvae ("grubs," "wire worms," or 
"borers") of the beetle family. 

1. Describe the beetle as to size, shape, and coloring. 

2. Describe the outer covering of the beetle. 

3. Into what regions is the body divided? 

4. How many eyes does it have? Simple or compound? 

5. Locate the antennae. Are they segmented? 

6. What is the food of the beetle? 

7. For what type of work are the mouth-parts adapted? 

8. Two wing covers protect the wings. Describe them as to si/<\ 
shape, and texture. 

9. How do they fit together? 

10. How are they held during the flight? 

20 



THE BEETLE 21 

11. Lift up the covers and describe the wings found beneath. 

12. How many legs has the beetle? 

13. To what body region are they joined? 

14. For what are they used? Do you find any special adaptations 
for this use ? 

15. How many segments in the abdomen? 

16. What are "grubs," "wire worms," and "borers"? 

17. Are beetles in general beneficial or harmful to man? 

18. Write a complete life history of the special beetle which you have 
studied. 



19. Make a drawing (X 5) of the entire beetle from the left side, 
labeling all parts. 



GENERAL STUDY OF INSECTS 

A collection of preserved specimens of the insect group 
should be available or the class may make a collection of 
living specimens. Let the group include as many as possible 
of the following : beetles, grasshoppers, dragon flies, bees, 
butterflies, moths, cicadas, true bugs, and flies. 

Answer each of the following questions for each insect 
studied. If preferred, the data may be recorded in tabular 
form. 

1. What is the insect's natural habitat? 

2. How many legs has it? 

3. How are they adapted for its special use? 

4. How many wings? 

5. How are they specially fitted to perform their work? 

6. What is the food of the animal ? 

7. How are the mouth-parts adapted to secure this food? 

8. What kind of metamorphosis docs the insect have? 

9. How does it escape its enemies? 
10. Is it harmful or helpful to man? 



2'2 



THE CRAYFISH 

Several live specimens should be caught by the students 
and put in aquaria in the laboratory where they may be 
observed and studied. Preserved specimens may also be 
used for some parts of the exercise. 

1. Describe the natural habitat of the crayfish. 

2. Where do they make their burrow? Why? 

3. What is the color of the living crayfish? 

4. Explain the value of this to the animal. 

5. Where is the skeleton of the crayfish? 

6. Of what advantage is this ? What disadvantage? 

7. How may a crayfish grow? 

8. How many body regions can you find? 

9. The anterior region is called the head-thorax and the posterior 
region the abdomen. 

10. Describe the bony covering of the head-thorax which is called 
the carapace. 

11. Is the body of the crayfish segmented? 

12. How many segments are there in the abdomen? 

23 



24 ANIMAL BIOLOGY 

13. In what directions are they movable? 

14. What is the last segment used for? 

15. How is it adapted for this work? 

16. How many pairs of legs are there? 

17. How many pairs have pincers? 

18. For what purpose does the crayfish use the first pair? 

19. How are they adapted for this purpose? 

20. What methods of locomotion does the crayfish employ? 

21. Which is best for food-gathering? For escaping enemi 
Why? 

22. The long "feelers" of the head are called antennae and the short 
ones antennules. 

23. How many of each does the crayfish have? 

24. Are they solid or segmented? 

25. Locate them with respect to the eyes. 

26. What seems to be their function? 

27. Are the eyes simple or compound? 

28. Touch one with a needle. What happens? 



THE CRAYFISH 25 

29. Of what advantage is this to the crayfish? 

30. What is the natural food of the crayfish and how is it secured? 

31. Feed the animal some little pieces of liver or fish and observe him 
eat. 

32. Locate the mouth. 

33. How many pairs of appendages do you find that aid in the 
eating process? 

34. Name and describe each pair. 



35. On the ventral side of the abdomen are located the swimmerets. 

36. How many pairs are there? 

37. For what are they used? 

38. Does the crayfish reproduce sexually or asexually? 

39. The first two pairs of swimmerets are long in the male and small 
in the female. Determine the sex of your specimen. 

40. With a medicine dropper let fall a few drops of carmine solution 
near the side of the crayfish just above the legs. 

41. What becomes of the carmine? 

42. Where does it reappear? 



26 ANIMAL BIOLOGY 

43. What organ is responsible for this circulation? 

44. Describe it as to structure, shape, and attachment. 

45. What benefit does the animal get from this current of water? 

46. Why are crayfish commonly found with their heads down 
stream ? 

47. Make a drawing (X2), labeling all body divisions and append- 
ages. 



48. Name some other animals closely related to the crayfish? 

49. Of what economic importance is this group to man? 



Dissection of the Crayfish 

Large preserved specimens should be provided for class 
use. If the lesson is to be a demonstration, a lobster would 
be preferable on account of size. 

1. The head-thorax is covered by a saddle-shaped bone called the 
carapace. 

2. Where is this attached? 

3. Carefully remove this, bringing to view the gills and gill chamber. 



THE CRAYFISH 27 

4. What appendages have gills attached? 

5. How many gills are in each chamber? 

6. Describe a gill as to form, structure, and functions. 



7. Are the gills outside or inside the body cavity? 

8. Make a drawing of the side view of the head-thorax with carapace 
removed, showing the legs with gills attached. 



9. Remove the body wall just back of the antennae and expose the 
two kidneys or green glands. 

10. Describe them as to shape and color. 

11. Where is the external opening? 

12. Remove the dorsal part of the body wall, taking care not to injure 
the heart, which lies just beneath. 

13. Describe the heart as to size, color, location, and function. 



14. Can you find any tubes running from the heart? 

15. What is their purpose? 



28 ANIMAL BIOLOGY 

16. Remove the heart and observe the organs of the digestive system. 

17. Describe the size, shape, position, and function of 

a. Mouth 

b. Oesophagus 

c. Stomach (two chambers) 

d. Intestine 

18. Make a labeled drawing of the body cavity (X2) containing all 
observed organs. 



19. Remove these organs and note the ventral nerve cord. 

20. Describe it as to length, size, and color. 



THE FISH 

Small perch or goldfish in jars should be placed where every 
student may observe and study them. 

1. The fish is a vertebrate animal. What does this mean? 

2. With what is a fish 's body covered ? 

3. How are these parts arranged? 

4. Name the distinct body regions of the fish. 

5. Locate the mouth. 

6. What is the fish's food? 

7.. Do all fish have teeth? Do they chew their food? 

8. Can a fish taste? Test with sand and fish-food. 

9. How many nostrils has a fish? 

10. For what are they used? 

11. Describe the eyes as to number and location. 

12. Are they movable? 

29 



30 ANIMAL BIOLOGY 

13. Does the fish have eyelids? May the eyes be closed? 

14. How are the eyes protected? 

15. Do the fish appear to hear? 

16. Locate and describe the operculum or gill cover. 

17. Under these covers are the gill chambers, in each of which there 
are usually four red gills. Each gill is an arch of bone covered with a 
fleshy fringe. 

18. Why does the fish continually open and close its mouth? 

19. Where does the water thus taken in escape? 

20. Explain fully how a fish respires. 

21. How many organs of locomotion can you find? 

22. How many are in pairs and how many single? 

23. Locate each of the following fins : Pectoral, pelvic, dorsal, anal, 
and caudal. 

24. After studying your specimens try to determine what the special 
use of each one is. 

25. Which is largest? Why? 

26. Which is used most? Least? 

27. Can a fish remain motionless in the water? 



THE FISH 31 

28. How is the fish protected from its enemies? 

29. Of what economic importance are fish? 

30. Name some fish common in your locality? 

31. How are the state and federal governments trying to protect fish ? 



32. Write a complete life history of a native fish. 

33. Make a drawing of the left side of a fish, labeling all parts. 



If possible secure a large fresh fish at a market and re- 
move the operculum carefully and expose the gill chamber 
and gills. 

34. How many gills can you see? 

35. Are they all alike? 

36. Describe one as to size, shape, color, and position. 



37. How do gills secure oxygen from the water? 



32 ANIMAL BIOLOGY 

38. Why do fish commonly lie in a brook with their head upstream ? 

39. Make a drawing of the head with operculum removed, labeling 
all parts. Show by means of arrows the path taken by water through 
the gill chamber. 



THE FROG 

Live frogs should be captured and kept in a moist box in 
the school-room. Each student should be provided with a 
specimen which has been chloroformed or preserved in a 
5% formaldehyde solution. The complete life history may 
be observed if frogs and tadpoles are secured in the spring 
and kept in an aquarium. 

Examine a live frog. 

1. What is the habitat of the frog? 



2. Describe the color of the frog. Is this an advantage or disad- 
vantage ? 



3. How is the ventral side colored? Why? 

4.. How does the frog feel when it is handled ? What causes this ? 

5. What methods of locomotion does the frog employ? 

6. Are the eyes movable? 



7. How many eyelids can you find ? Try touching the eyeball with 
a pencil. 



8. Why does the skin under the mouth move? 

33 



34 ANIMAL BIOLOGY 

9. Can the frog hear? Make a test. 

10. Put some insects (flies, grasshoppers, or bees) in the cage and de- 
scribe the way the frog secures its food. 

Study the preserved specimen closely. 

11. How many body regions can you distinguish? 



12. Open the mouth. How does it compare in size with mouths of 
other animals we have studied ? 



13. Draw out the tongue. What is its shape? 

14. Where is it fastened? 

15. Can you find any teeth in the frog's mouth? 

16. Make a drawing (X2) showing the lower jaw and tongue. 



17. Locate the nostrils. For what are they used? 



18. Using a horsehair or probe, determine whether or not they open 
into the mouth. 



19. Explain exactly how the frog breathes. 

20. How many toes are on the front foot I 



THE FROG 35 

21. Are there the same number on the hind foot? 

22. For what purpose is the front leg used? 

23. Why should the hind legs be better developed? 



24. Describe the special adaptations of the hind leg for leaping. For 
swimming. 

25. Make a drawing, natural size, of the fore leg and the hind leg of a 
frog extended. 



26. Write a complete life history of a frog, giving in detail the stages 
of development and their accompanying changes in form, manner 
of breathing, and so forth. 



Dissection of a Frog 

With the scissors carefully cut around and remove the skin 
on the ventral side of the abdomen. Then with the scalpel 
and scissors very carefully remove the entire muscular wall 
on the ventral side, being careful not to injure the organs 
lying just beneath. 



36 ANIMAL BIOLOGY 

27. Is the body cavity of the frog divided by a muscular partition or 
diaphragm ? 



28. Locate and describe the lungs and the heart in the anterior end 
of the body cavity. 



29. The large reddish brown organ lying close to the lungs is the 
liver. Into how many parts or lobes is it divided ? 



30. Describe it as to size, shape, color, and location. 



Carefully remove these parts and dissect out the entire 
alimentary canal. 



31. Describe each part of the canal as to relative size, shape, color, 
ind function. 



32. Open the stomach and note the contents. 



33. What is the food of the frog? 



THE FROG 37 

34. Is the frog harmful or beneficial to man? 



35. Make a labeled drawing, natural size, of the frog with the entire 
ventral side removed, showing all the organs in place. 



MOUNTED BIRD 

1. Examine a mounted specimen of a bird. With what is it 
covered ?. 

2. What advantage have feathers over scales as a covering for birds ? 

3. How are feathers a good protection against cold weather? 

4. Notice the shape of the bird's body. 

5. Is this shape favorable for flying? How? 

6. Notice the beak. What kind of food is it fitted for handling? 

7. Notice the wings. Are they placed advantageously for flying? 
How? 

8. Notice the tail. In what way is a tail similar to a rudder on a 

boat? 

9. Is a rudder necessary for a flying machine ? Why ? 

10. Show how a bird is like a flying machine. 

11. Show how a bird is different from a flying machine. 

38 



MOUNTED BIRD 39 

12. Notice the feet. How are they adapted for perching? For 
offense ? For defense ? For food-taking ? 



13. Sketch a side view of a bird, labeling beak, nostril, eye, ear (no 
external shell present), and feet. 



14. Compare the beaks of different birds, such as hawks, sparrows, 
herons, kingfishers. 



15. Compare feet of different birds, such as a hen, duck, hawk, 
canary, and crow. 



16. Name some birds that are excellent fliers. Are their wings long ? 



17. Name some birds that are good runners. Are their legs long and 
strong ? 



FIELD TRIP TO STUDY BIRDS 

Note to Teacher. No better way of studying birds is offered 
than by .field trips. The best time to study birds is early in the morn- 
ing from 4 to 6 or from 5 to 7. Another good time is in the afternoon 
from 5 to 7. On these trips a report should be made out by each 
pupil, giving the information called for. Modifications of the following 
forms will afford material for several trips. 



■Plate A- 



Pcpoot roo loamncATioN or Bmnn 



I 

1 



fe 
g 



^ 3 



§ 









is 



§1 
11 



e h 






fr 



Ono/e 



Purple finch 



Su/JT 



Golden Crowed 
Kinglet 



Bluebird 



Flicker 



Rebut 



1 Wa* Ouit tomttc cJandwto ^w i* ttutc rut mmT 



10 



FIELD TRIP TO STUDY BIRDS 



41 



Plate B- 






— "Report for feeding station — 
















i 


i 


Line of flight 
touards food 


t 

51 


Manner of — 
coming to food- 


-5 
id 


1 

1 


"b" 

1 

| 


i 


1 


i 


Dcuny Vbodpcckr 
























Hairy Voodpeckcr 
























Nuthatch 
























Chickadee 
























Broun Creeper 
























Song sparroo) 
























House or 
English Sparrow 
























Vodm 
























Crackle 

























Plate C- 






- Report for Birds in 


Nesting Seasor 


i — 










r 


"5 

1 


1 


£ggs 


Adults 


Young 


fa 

I 


c 

c 
in 


1 

-Cl 


1 


1 

N 


\ 
I 


I 


1 

V) 

r 


i 


UQbm 


























Chipping Sparrou 


























Oriole 


























Grackle 


























fcadou LarH 


























Phoebe 


























Cat Bird 


























Mourning Dove 


























House Sjomoij 



























42 



ANIMAL BIOLOGY 



Vlate D— 



r 

— "Report on a single pair of Birds feeding their young — 





\ 




1 
I 


\ 

Si 

1 


/lumber of times each 
/lest ling is fed- — 


Direction from uhich 
Adurts approach nest- 


1 

! 

"*> 

o 


I 


i 


i 






1 




i 

1 


1 

I 


1 


3:/ 5 


























1 






9 20 
































9-21 
































$ 28 
































930 
































9 40 
































9 43 


























. 






947 
































9-33 

































Plate E- 






Report for 


Seasonal Activities of Birds — 












1 

1 


1 

i 


a 
s 


O 


1 


Color of young 


Color of Adult 




T3 

1 


8 

1 


CO 

c 

5 






O 
§ 


ft. 


1 


Robin 






























Bluebird 






























Clapping Sparwu 






























Gold Finch 






























Cedar Bird 






























Bobolink 






























Song Sparrou 






























Sandpiper 






























ttoux Sporrw 































MAMMALS 

From a skeleton or chart of a skeleton study the dog or 
cat. 

1. Notice the framework of bones. Of what use to the living is this 
framework ? 



2. Notice the attachment of the legs. Of what use are these legs 
to the living animal? How are they united to the framework? 



3. Notice the forms of bones that may be classed as long bones, flat 
bones, and irregular bones. Name uses of each class of bones. 



4. Which class is best adapted for protection ? Name some of these. 



5. Which class is best adapted for attachment of large muscles? 
Name some of these. 

6. Which is best adapted for attachment of small muscles ? Name 
some of these. 

7. Compare the bones of front and hind legs as to number, general 
form, and use. 



8. How can you account for the difference between the shape of 
some of these bones that occupy the same relative position in a front and 
a hind leg? 

43 



44 ANIMAL BIOLOGY 

9. Notice the inside toe of each front fool . How does it compare in 
strength with the other toes of the same foot ? Is t his inside toe (thumb) 
of any use to the living animal for supporting weight or holding food"/ 



10. Look for the corresponding toe of the hind foot. Do you find it ? 
If not, how would you account for its absence? Is there a tendency for 
useless structures to disappear from animals? 



11. Examine the teeth of the upper and lower jaw. How does the 
number on each jaw compare? How do the forms of opposing teeth 
compare? Compare the front teeth (incisors) with the molars. How 
would use account for any differences you find ? 



12. Examine the eye teeth (canines) just outside the incisors. 

Show for what these teeth are adapted. 

13. Compare the vertebrae of the neck and tail. How would US6 
account for the difference in size? 

14. What adaptation of the skeleton in general can you make out 
that gives the animal speed in travel? 

15. In how many ways is the human skeleton like the skeleton you 
have just studied? 



THE PARAMECIUM 

A. Reaction to Stimuli 

Paramecium or slipper animals may be seen by the naked 
eye in a hay infusion as tiny white specks moving rapidly 
through the water. Deposit a drop of the infusion containing 
the animal on a glass slide and examine under the compound 
microscope. While the Paramecium has no sense organs or 
nervous system, it will react to a variety of stimuli. Watch 
an individual as it swims about. 

1. What happens when it bumps into a grain of sand? 



2. Is there a different response if it comes in contact with a piece of 
vegetable matter? What does the animal do? 



3. Slightly jar the slide. What change occurs in the animal? 



4. How does the Paramecium react wnen a warm needle point is 
brought near it? 



5. By reflecting a strong shaft of light from a mirror, try to dis- 
cover whether or not the Paramecium is affected by ordinary light. 



6. What difference can you discover in the reactions to gentle and 
severe stimuli? 



45 



46 ANIMAL BIOLOGY 

7. Make a drawing showing by arrows what happens when a Para- 
mecium runs into an obstacle. 



B. Food-taking 

Deposit a drop of infusion containing a Paramecium on a 
glass slide and carefully push a wisp of cotton fibers into the 
drop before putting on the cover glass. These will prevent 
the free swimming of the Paramecium, and it may be studied 
more closely. Locate an animal near the center of the field 
and carefully drop some finely powdered carmine into 
the drop of water with it. It will be seen that the pigment 
circulates with certain water currents. 

1. Trace the course the carmine takes. 

2. Describe the body structure for taking in food. 

3. What creates these currents? 

4. How are these an aid in food-getting? 

5. What is the natural food of the Paramecium? 

6. Can the Paramecium recognize food from sand? 

7. What are food vacuoles? 

8. How many can you find? 

9. In what part of the body are they located? 



THE PARAMECIUM 47 

10. Why are they not all of the same color? 

C. Excretion 

Continue the examination of the Paramecium as described 
in B. Look for clear, round spots of considerable size 
called contractile vacuoles. 

1. How many do you find? 

2. In what part of the body are they found? 

3. Is this location permanent? 

4. What relation do they bear to food vacuoles? 

5. Explain how they get rid of contents. 

6. Watch one for several minutes. How many times does it contract 
per minute? 

D. Cell Structure 

Locate and examine a Paramecium under the high power 
of the compound microscope. 

1. Has the Paramecium a definite shape? 

2. May the animal alter its shape? 

3. Can you find any divisions or partitions in the animal? 

4. Of how many cells, then, is it composed? 



48 ANIMAL BIOLOGY 

5. Has the Paramecium a definite cell wall? 

6. What do you find covering the whole body ? Describe them 

7. Are they longer on any particular part than elsewhere? 



8. What is the groove used for ? 

9. How is it specially adapted to this function? 

10. How many kinds of vacuoles can you find ? 

11. Compare them as to number, size, location, and purpose. 



12. The nucleus will be visible if some stain is dropped into the in- 
fusion. 

13. Describe the shape of the nucleus. 

14. The Paramecium is a typical protozoon. Name its essential 
characteristics. 



15. Make a drawing (4" long) of the Paramecium, labeling cell wall, 
cilia, food groove, nucleus, contractile vacuole, and food vacuole. 



THE SPONGE 

Examine a specimen of the sponge called grantia, which 
may be secured from dealers in biological supplies. This is 
one of the simpler animals composed of many cells. 

1. What is the length of the grantia? 

2. How does this compare with the width ? 

3. What is the shape of the body? 

4. Notice the sharp, needle-like structures which project from the 
body. They are called spicules. 

5. Of what mineral substance are they composed? 

6. Of what use are they to the sponge? 

7. Observe the shapes of some spicules under a compound 
microscope, and make several drawings of the shapes observed. 



8. One end of the sponge is always attached to a rock or other object. 
Can you see where your specimen was torn loose? 

9. Describe the other or free end of the animal. 

49 



50 ANIMAL BIOLOGY 

10. With a sharp knife cut the specimen in two lengthwise, making 
a longitudinal section. The hollow space or cavity is called the cloaca. 

11. Can you see any pores in the side of the body? 

12. Water flows continually through these pores into the cloaca and 
out through the opening in the free end called the osculum. 

13. Of what use is this water current to the sponge? 

14. What creates these currents? 

15. What is the food of the grantia? 

16. Describe any evidence of budding which you may find in your 
specimen. 



17. The animal sometimes reproduces sexually. 

18. Of what economic value is this animal family ? 

19. Make a drawing, actual size, of a grantia. 



20. Draw a longitudinal section of the sponge (X5) labeling cloaca, 
pores, osculum, and spicules. Show the water currents by means of 
arrows. 



HYDRA 

Living hydras may be found clinging to the submerged 
stems of water plants in most localities that have shallow 
ponds. Look at a specimen which has not been disturbed 
for some time. 

1. How long is it? 

2. Touch it lightly. What change occurs? 

3. How great is the difference in size? 

4. At the free end of the body may be found "arms" or tentacles. 

5. How many does the animal have? 

6. How are they arranged? 

7. For what are these tentacles used? 

8. Describe their movements. 

9. The mouth is in the center of the group of tentacles and leads to 
the hollow interior of the body. 

10. What is the natural food of the hydra? 

11. The body wall is composed of three layers : an outer, a middle, 
and an inner. 

51 



52 ANIMAL BIOLOGY 

12. In which layer must digestion occur? 

13. How do the cells of the other layers feed? 

14. What is meant by "division of labor"? 

15. What becomes of the unused part of the food? 

16. Can you distinguish any signs of reproduction by budding? 



17. The hydra also reproduces sexually. Look for ovaries and sper- 
maries, which may be seen as little lumps on the side of the body, the 
spermary usually being nearest the free end. 



18. If you can find them, describe them as to shape, size, and location. 



i 



19. What is the difference between sexual reproduction and budding? 
Explain. 



20. How does the hydra differ from the grantia? 



21. How may a hydra protect itself from its enemies f 



HYDRA 53 

22. Make a drawing (X4) of a hydra extended, and label base, 
mouth, tentacles, body cavity, budding hydra, and spermary and 
ovary, if found. Trace by means of arrows the path of food eaten by 
the animal. 



23. Draw to the same scale the same hydra contracted. 



THE EARTHWORM 

Take a short trip into a meadow to obtain living earth- 
worms. As specimens are found, study the natural habitat. 

1. How can you recognize earthworm burrows? 

2. How deep did you dig to find them? 

3. In what kind of soil did you find most worms? 

4. Why are they so common after rains? 

5. How do they offer resistance when dragged from their burrows? 

The specimens secured should be placed in a pail of moist 
(not wet) earth and carried to the class room. Place cadi 
worm on a piece of wet blotting paper and study it. 

6. Distinguish the anterior and posterior ends and the dorsal and 
ventral surfaces. 



7. What is the general shape of the body? 

8. What is the difference in shape between the anterior and posterior 
ends ? 



:,i 



THE EARTHWORM 55 

9. How does the anterior end differ from the posterior end as to size 
and color? 

10. By touching it with a needle, determine which end is most sensi- 
tive to touch. 

11. What is the general color of the worm? 

12. Is this an advantage or a disadvantage? Explain. 



13. Bodies composed of ring-like parts are said to be segmented. Is 
the earthworm segmented? 

14. Are all segments the same size? 

15. How many segments does your specimen have? 

16. Is this number the same in all earthworms? 

17. When the animal moves what is the action of the segments? 

18. How many setae or bristles on each segment? 

19. How are they arranged? 

20. Explain how they assist in locomotion. 



21. Does the same end always go forward? 

22. Of what advantage is the body slime? 



56 ANIMAL BIOLOGY 

23. What is the food of the animal? 

24. Locate the mouth. Of what advantage is this position? 

25. Has the worm hard jaws? Why? 

26. The enlarged band about the worm is called the clitellum. It 
forms a case for the eggs when they are laid. 

27. Nearest which end is the clitellum located? 

28. Of how many segments is it composed ? 

29. Does it form a complete ring? 

30. Do all the specimens you have secured have a clitellum? 

31. Does the earthworm reproduce sexually or asexually? 

32. Work out a scheme to discover whether earthworms prefer light 
or darkness. 



33. How is the earthworm protected from its enemies? 



34. Why cannot earthworms survive drying? 

35. Where are they in very hot, dry weather? 

36. How do worms benefit the soil? 



THE EARTHWORM 57 

37. Do they injure plants or animals? 

38. Write a complete life history of the earthworm. 



39. Make a drawing showing a lateral view (X2) of the earthworm, 
labeling mouth, segments, setae, and clitellum. 



Dissection of the Earthworm. 

Place the preserved specimen in a shallow dissecting pan 
partly filled with water. 

1. With the scissors cut along the middle of the ventral surface from 
the anterior end to the posterior. 

2. Pin the anterior end down to the wax and, working under water, 
carefully pull back the body wall and pin it back to the wax from the 
anterior to the posterior end, thus disclosing all body organs. 

3. Describe the tiny ventral nerve cord. 

4. What is the color and relative size of the ventral blood vessel? 

5. Remove these and notice the various organs of the digestive 
system. 



58 ANIMAL BIOLOGY 

6. Briefly describe the size, shape, position, and functions of 

a. Mouth cavity 

b. Pharynx 

c. Oesophagus 

d. Crop 

e. Gizzard 

/. Stomach-intestine 

7. Make a drawing (X4) of the dissection at this stage, showing 
all organs labeled and in place. 



8. Remove the digestive organs and note the large, dorsal blood 
vessel. 

9. Is it larger or smaller than the ventral vessel ? 

10. How many loops or "hearts" can you discover? 



THE STARFISH 

Secure at the seashore or through a dealer enough speci- 
mens of the starfish so that each student may have one. 
These may either be preserved in formaldehyde solution or 
dried, and if carefully handled will last for years. 

1. Describe your specimen accurately as to size, shape, color, and 
general appearance. 



2. How many arms or rays does your specimen have? 

3. Compare with other specimens used by the class. 

4. How do you account for the differences in size of the rays on 
some specimens ? 

5. Define "regeneration of parts." 

6. What kind of skeleton does the starfish have? 

7. Describe the outer covering of the animal. 



8. What difference do you notice between the dorsal and ventral 
surfaces? 



59 



60 ANIMAL BIOLOGY 

9. The central part of the starfish is called the disk. On the dorsal 
surface of the disk may be found a wart-like growth called the madre- 
poric body. Describe it as to location, size, shape, and color. 



10. Does it appear to be solid or porous? 

11. Suggest a possible use to the animal. 

12. Note the groove on the ventral surface of each ray. It contains 
the tube feet. Describe these as to number, size, and shape. 



13. With what are the sides of the groove covered? 

14. Why do the tube feet need so great a protection? 

15. How does the starfish move from place to place? 

16. Try to distinguish an eye spot at the end of each ray. What are 
the advantages of this location ? 

17. In the center of the ventral surface is the mouth. Sow is it pro- 
tected ? 

18. Possibly you can see inside a gray bag, the stomach. How doc? 
the food get into the stomach ? 



19. What is the food of the starfish? 



THE STARFISH 61 

20. Describe in detail how a starfish would kill and eat its prey. 



21. Of what economic importance is this animal to man? 

22. Suggest ways to check the destruction caused by the starfish. 



23. Make a drawing, natural size, of the ventral surface of the star- 
fish and label rays, spines, tube feet, eye spot, mouth, and stomach. 



FRESH-WATER CLAM 

Secure from local streams or through a dealer several 
specimens of fresh-water clams or mussels. Put each speci- 
men in a jar of water in which there are several inches of 
sand and leave undisturbed for several hours before using. 

1. What is the habitat of the fresh-water clam? 

2. Describe a specimen as to approximate size, shape, color, and po- 
sition. 



3. How many parts (called valves) do you find in the exoskeleton ? 

4. They are hinged together ; locate the hinge when the animal is in 
a natural position. 

5. Can you see any evidence that the clam has moved about in the 
jar? 

6. How are clams fitted for locomotion? 



7. Let one of the class quickly lift a clam from its resting place. De- 
scribe the foot as to size and color. 



8. Near one end of the shell opening you will observe some exterior 
openings ; how many ? 

9. These are called siphons. By releasing a drop of red ink 

with a glass tube near the siphons determine the direction ot" flow 
of any possible water currents. 

62 



FRESH-WATER CLAM 63 

10. Why does the clam need water? 

11. Of what does the clam's food consist? 

12. How is the clam protected? 

13. Name some relatives of the fresh-water clam. 

14. Of what economic importance is this group to man? 

15. Draw (X2) the lateral view of the fresh-water clam, labeling 
valve, hinge, foot, inhalent siphon, and exhalent siphon. 



INTERRELATIONS OF PLANTS AND ANIMALS 

THE BALANCED AQUARIUM 

A balanced aquarium may be made by the class. If the 
school does not possess regular aquaria, these may be made 
as a class project l or battery jars may be used. The 
bottom of the aquarium should be covered with sand, and 
such water plants as are common in the locality should be 
planted in it. Eel-grass, bladderwort, watercress, the 
stoneworts, and others are common in New York. A plant 
called parrot 's feather, commonly used in fish globes, may 
be obtained from a florist and used to advantage. Duckweed 
may later be placed on the surface of the water. Having 
planted these, the sand should be covered with small 
stones or gravel and water carefully added. 

A field trip to a pond or sluggish stream will provide plenty 
of animal life. Water beetles, pond snails, crayfish, p< >lliwogs, 
and small minnows may be used and goldfish may be added 
if desired. 

In a properly balanced aquarium it will be necessary 
only to add water on account of loss by evaporation. 

Study closely the life processes occurring in a balanced 
aquarium. 

1. What gas do animals require for respiration? 

2. When this has been used and changed by the body, it is given off 
as what gas? 

» Cornel] Teachers Leaflet No. 11, May, 189v 

64 



THE BALANCED AQUARIUM 65 

3. In a balanced aquarium what becomes of this product? 

4. What raw materials are necessary for the plant to manufacture 
starch? 

5. On a sunny day look for tiny bubbles on the surfaces of the 
plants. What gas is this ? 

6. By what organism is it utilized in the aquarium? 

7. As the animals live and grow, from what source can they secure 
their food? 

8. What becomes of the nitrogenous wastes of the animals? 

9. If a plant or animal chances to die, how is it disposed of, 
naturally ? 

10. Define symbiosis. 

11. Is it present in a balanced aquarium? 

12. Explain how plants, other than aquaria plants, depend upon 
animals. 

13. In what ways are animals dependent upon plants? 

14. Make a diagram showing a plant and an animal of a balanced 
aquarium and by means of labeled arrows show the interchange of essen- 
tial materials. 



THE HAY INFUSION 

Gather a small bunch of dry grass or hay and put it to 
soak in a glass of water. Leave this in a warm room for 
several days and then examine carefully. By allowing the 
water to evaporate, a productive infusion may be kept 
and used from year to year by adding water to the dried 
hay and scum. 

1. What apparent changes have occurred in the water? 



Examine a drop containing a bit of the hay under the 
compound microscope. Great numbers of small one-celled 
plants called bacteria will be seen. 



2. How did they get into the infusion? 

3. What do they appear to be doing? 

Search carefully and find some simple one-celled animals 
called protozoa. 

4. How many different kinds can you find? 

5. Where could they have come from? 

6. Try to see one eat. Of what does its food consist? 

60 



THE HAY INFUSION 67 

7. Describe its activities. 



8. How do the protozoa compare with the bacteria as to size and 
number? 

9. By examining a drop from the infusion at intervals of several days 
determine whether or not the numbers of the protozoa are increasing. 

10. Suggest reasons why this is true. 



11. What effect does this have on the numbers of the bacteria? 

12. How might a balance of life in a hay infusion be secured? 



PLANT BIOLOGY . 

FLOWERS 

Fall Study 

Parts of a Flower 

Material: Select nasturtium blossoms if possible when 
the study is undertaken in the fall. 

1. Notice the outer parts, sepals. How many are there? 

2. Examine the inner, more highly colored parts, petals. How 
many are there ? 

3. Compare the shape of the different petals. Compare the upper 
two and the lower three. Notice the fringe. 

4. What advantage might this fringe be to the flower in offering a 
barrier to crawling insects? 

5. Notice the stripes on the upper petals. Towards what do they 
converge? Examine this long tube, the nectar spur. 

G. What advantage is there to the flower in having the nectar at the 
bottom of a long nectar spur? Think of this in connection with short- 
tongued and long-tongued insects. 

7. Make a sketch to show side view of nasturtium flower. Label 

all parts. 

68 



FLOWERS 69 

8. Notice the thatched form of sepals and petals over the top of the 
flower. How might this arrangement assist in keeping rain from the 
nectar spur? 

9. Remove sepals and petals from (1) a flower just opened, (2) a 
flower in prime condition, and (3) a faded flower. Notice the number 
of stamens in each. How many? Notice the anthers in each of the 
flowers. In which flowers do you find the largest anthers? Do all the 
anthers mature at the same time? If they do not, how would this 
assist in gaining pollination? 



10. Compare the pistils in each of the flowers just examined. In which 
of the flowers do you find the three-pronged stigma ? If more than one 
stage shows a three-pronged stigma, which one has the freshest looking 
stigma? 

11. Do anthers apparently shed their pollen before or after the three- 
pronged stigma is developed? 

12. When the anthers and stigma mature at different times we have 
an illustration of dichogamy. 

13. Make a sketch to show the three conditions of stamens and pistils 
as found in the different nasturtium flowers just examined. 



THE COMPOSITE FAMILY 

The Dandelion 

Note to Teacher. — Explain the composite family to the class before 
the laboratory period and emphasize the main differences between the 
dandelion t}'pe and the sunflower type. 

1. On a sunny day, just before the laboratory period, bring in a quan- 
tity of dandelion heads in different stages of development. Select some 
just opening, others in full bloom, and others beginning to open. 

2. Examine a head that is beginning to open. 

3. Notice the center cluster of unopened florets (the individual 
flowers of the head). How do they compare with the florets around them 
in form ? 

4. Remove a floret from the outer border and examine. Find the 
small, strap-shaped corolla with small teeth at the upper end. I se a 
hand lens and count these teeth. How many do you find.' 

5. Above the attachment of the corolla to the floret, notice the 
cylindrical form (the hollow cylinder of united stamen- with anthers 
inside. This is difficult for the beginner to determine. 

6. Above the stamens look for the T-shaped stigma and part of 
the style. The style continues through the hollow cylinder of Btameof 
to the ovary. 

7. Note the ovule at the bottom and above it the group of small 
hairs, the calyx. Later this calyx becomes the pappus of the fruit. 



70 



THE COMPOSITE FAMILY 71 

8. We now have the complete flower : the corolla (the united petals), 
the stamens (the united cylinder of the center), the pistil with the 
T-shaped stigma, style, and ovary (ovule), and the hairy calyx. 

9. In the younger florets in the center what parts named above can 
you make out? 



10. Select different stages in the development of florets, beginning 
with the younger ones of the unopened center and ending with the florets 
that show an elongation between ovary and old corolla. Make a selec- 
tion of five or six in different stages of development. 



11. Sketch the series above and label all parts that you can make out. 



12. Another composite is the sunflower. Compare the corolla of the 
dandelion with the corolla of a sunflower floret. Notice that the corolla 
of the sunflower is not on one side as in the dandelion, but surrounds the 
floret. How many tips to the sunflower corolla? 



13. Notice stamens. How do they compare with those of the dan- 
delion? 



14. Notice pistils. Compare those of the dandelion with those of 
the sunflower. In what ways are they alike? What are their dif- 
ferences ? 



15. What takes the place in the sunflower of the hairy calyx of the 
dandelion? 



16. Compare the outer florets of the sunflower, that is, the ones that 
bear the colored ray flowers, with the outer flower of the dandelion head, 
What is the difference? 



72 PLANT BIOLOGY 

17. Compare the other composites like the wild asters, goldenrod, 
wild sunflowers, china asters, marigolds, cosmos, bachelor's buttons, etc., 
to see if they are more like the sunflower or dandelion in the form of their 
heads. 



INSECT-POLLINATED FLOWERS 

Spring Study 
To study flowers of cherry : 

1. Examine the flower. Notice the green outer envelope of sepals 
that make the calyx. How many are there? 

2. Find these sepals in the bud of a flower. What purpose do they 
appear to serve ? 

3. How many petals (the row of parts just inside the calyx) do you 
find? Examine several cherry blossoms. Do you find any with four or 
six petals? It is not unusual to find such variation. 

4. Examine the next group of parts inside the corolla (the name 
given to the petals taken together). These are stamens. How many 
would you estimate there were of these ? They vary in number. Ex- 
amine a stamen with a hand lens. Make out the knobbed end at the 
top, known as the anther, and the slender stem that supports it, the fila- 
ment. 

5. By using a hand lens are you able to tell how the anther opens 
to let out the pollen? 

6. Examine the central part of the flower, the pistil. This is made 
up of three parts ; the upper end is the stigma. The slender stem that 
supports is the style, and the small forming cherry at the lower part is 
called the ovary in the flower. 



73 



74 PLANT BIOLOGY 

7. Examine several cherry blossoms to see if the stigma is glistening 
with moisture at the same time the pollen is seen on the anthers. When 
the stigma glistens, it can germinate pollen grains — this is the beginning 
of fertilization. If the pollen that touched the stigma came from the 
same blossom it would be self-pollinated. Are cherry blossoms self- 
pollinated? Give reasons for your answer. 

8. If the stigma and anthers mature at different times, the flower- 
are dichogamous. Are cherries dichogamous? Can dichogamous 
flowers be self-pollinated ? Give reasons for your answer. 



9. If cherries are cross-pollinated are they pollinated by insects or 
wind? Give reasons for your answer. 



10. Compare blossoms of plum, peach, or apricot with the cherry 
blossom. What are the main differences? 



STUDY OF WIND POLLINATION 

1. Select catkins from the stamihate cottonwood (a dioecious 
form). These are reddish in color and short. 



2. Examine the catkin to determine the anthers. How are they 
arranged on the catkins? 



3. Make a sketch to show the staminate catkins leaf buds and other 
features of the cottonwood stem. 



4. Select catkins from the pistillate cottonwood. These are slen- 
derer than staminate catkins and are greenish in color. 



5. Examine these catkins to determine the pistils. Make out 
stigma, style, and ovary. 



6. Do you find calyx or corolla on either kind of catkins ? What ad- 
vantage in this ? 



7. Are these catkins adapted for wind pollination or insect pollina- 
tion? Give reasons for your answer. 



75 



76 PLANT BIOLOGY 

8. Do these catkins have a strong odor? Would a strong odor be 
of any use in pollination? 

9. Have these catkins any striking coloration? Would striking 
colors aid in pollination? 

10. Is pollen abundant ? Is it dry and dusty ? What advantage in 
pollination ? 

11. Is the stigma large and sticky? What advantage in pollination? 



WIND-POLLINATED FLOWERS 

Spring Study 

The Oak, a Monoecious Form 

1. In the oak the staminate flowers appear early in the form of cat- 
kins. The pistillate flowers are not made out as easily nor as early in 
the season. 



2. Examine the catkins of oak as soon as they are powdery (pollen 
forming) . 



3. How are the anthers attached? Do you find calyx or corolla? 
Remembering the purpose that the corolla serves in pollination, how is 
it that the oak blossoms do not have a corolla ? 



4 . Sketch a cluster of catkins . (Use a hand lens to make out details . ) 



5. Look on the newer parts of the season's growth for pistillate 
flowers. These flowers are really the small acorn with the stigmata and 
styles attached. 



6. How many parts are there to the stigma? 

77 



78 PLANT BIOLOGY 

7. What advantage in pollination is there in having a large, feathery 
surface for the stigma? 

8. Examine the surface of the stigma and describe it. 

9. What advantage in pollination in having dry, abundant pollen? 
What chance of waste of pollen in such a case ? 

10. Is the pollen dry or sticky? Under what circumstances would 
sticky pollen be advantageous? 

11. Make a sketch to show the form of the pistillate blossom. 
Label all parts. 



12. Compare blossoms of pignut, hickory, black walnut, or English 
walnut with the blossoms of the oak. What are the main different' 



13. What advantage have trees that are wind pollinated over 1 1 
that are insect pollinated? 

14. How do you account for the lack of striking colors or fragrance 
in the wind-pollinated flowers? 

15. What advantage is there in having thr blossoms form before the 
leaves are fully developed? 



SEEDS AND FRUITS 

1. Compare a number of selected dry marrow beans. (Any other 
large bean will do.) 

2. In what respects are they all alike? 

3. In what respects do they differ? 

4. Outside features : 

a. Notice the scar, hilum, where the bean was attached to pod. 

b. Near the hilum notice a small opening. (Use hand lens.) 
This is the micropyle. 

c. A raised portion of the surface near the hilum indicates a 
union of the seed coats. This is the chalaza. 

d. A line or ridge joins the hilum with the chalaza. This is the 
raphe. 

5. Soak in water over night enough beans for class use. 

6. Make a sketch to show the outside features of the bean, label- 
ing hilum, micropyle, chalaza, and raphe. 



7. Remove the peel. Notice the two parts inside. These are the 
cotyledons. These cotyledons hold the loosely attached embryo. The 
sprout is the hypocotyl and the leaf-like part is the plumule. Separate 
the cotyledons. 



79 



80 PLANT BIOLOGY 

8. Sketch one of the cotyledons with its attached embryo. Label 
cotyledon, hypocotyl, and plumule. Use a lens to show the veining of 
the plumule. 



9. Examine some beans that have been germinating for several 
days. Does the plumule or the hypocotyl form the lea v. The stem ".' 

The roots? 

10. If time permits, germinate the scarlet runner beans, lima beans, 
and others. Compare the hypocotyls and plumules of each. 

11. Make a study of soaked peas following the questions and direc- 
tions for beans. 

Castor Bean (Ricinus) 

1. Examine castor beans and compare with marrow beans. 

Note : Castor beans and marrow beans are not closely related. In 
fact peas and beans belong to the same family (pulse family), while 
castor beans are in another family (spurge family). 

2. How do the different castor beans compare in color and markin. 

3. Examine the surface markings of castor beans. 

a. Notice the thickened extension like a small handle. Thia is the 
caruncle. (See Beal's Seed Disp< rsul, page 70.) 

b. Find the hilum near the caruncle where the castor bean hi 
attached. 

c. Find the chalaza near the end opposite the caruncle. 

d. Trace the faint line from hilum to caruncle. Thia is the 
raphe. 



SEEDS AND FRUITS 81 

4. Sketch a view of the castor bean to show caruncle, hilum, chalaza, 
and raphe. 



5. Compare this drawing with the similar drawing of the bean. 

6. Remove the peel (testa) and notice the delicate, white inner- 
lining, the endopleura. How does this feature differ from the bean? 

7. Open up the interior. Can you find the embryo? Compare 
with marrow bean. 

8. Notice, if possible, the faintly veined plumule covering the 
cotyledon. Compare this feature with marrow bean. 

9. Notice short straight hypocotyl at one end. 

10. Note that in the castor bean the cotyledon has the veining and in 
the marrow bean the plumule has the veining. 

11. The bulk of the castor bean that holds the food is the endosperm. 

12. What holds the food in marrow bean? 

Dent Corn 

1. Examine several kernels of dent corn. 

Note : Dent corn has long kernels. It is sometimes called western 
corn. There is a dent in the broad end of the kernel. 

2. Compare the two broad sides of several kernels of corn. How do 
they differ? 



82 PLANT BIOLOGY 

3. Examine the corn to find the silk scar near the broad end. 

Note : This can be made out best by looking at an car of green corn 
and tracing the silk thread to the attachment of the kernel on the cob. 

4. Under the depression on the broad side is the scutellum or 
cotyledon. 

Note : This can best be seen when the kernel is cut. Make out the 
embryo in the center of the depression. 

5. The hilum is not present, but the seed stalk at the lower end of 
the kernel takes its place. 



6. Make a sketch to show silk scar, embryo, scutellum, and seed 
stalk. 

7. Cut in two a kernel of soaked corn. Cut this evenly through 
the depression. 

8 Examine the cut edge and find directly under the depression the 
split scutellum. Notice behind this scutellum the light colored area. 
This is the endosperm. 

9. In front of the scutellum notice the embryo made up of three 
parts : First the plumule pointing toward the broad end second the 
root sheath pointing toward the seed stalk, and third the hypocotyl 
near the attachment of embryo to scutellum. 

Note : This is not easily seen, and the teacher may need to point 
this out in favorable specimens. 

10. Make a sketch to show the cut edge of the kernel of corn and label 
endosperm, scutellum, plumule, hypocotyl, root sheath, and seed stalk. 



STUDY OF GERMINATION 

Direction: Place in soil, moss, moist sawdust or damp 
cotton, a few beans, peas, castor beans, squash seeds, corn, 
etc., at intervals of four or five days. At the end of a month 
you should have seedlings of each in various stages of develop- 
ment. Arrange the seedlings of each in a horizontal row 
in order of age or growth from left to right. Sketch each 
of these and label as follows : hypocotyl, arch of the hypo- 
cotyl, cotyledon, plumule, brace roots, primary root, secon- 
dary root. 

Note : Use such of these terms or additional terms as are needed to 
label the drawing properly. See Figure 209, page 221, Biology for High 
Schools. 



83 



TESTS FOR FOODSTUFFS IN SEEDS AND FRUITS 

Test for Grape Sugar (Dextrose) 

Material: Fehling's solution, test tubes, gas or alcohol 
burner, mortar and pestle. 

Experiment : 

1. Crush five or six dry peas in the mortar (use late varieties, as they 
usually have more sugar). 

2. Boil in a test tube with water for five minutes. 

3. Heat about 10 cc. of Fehling's solution in another test tube. If 
no yellow color develops, the solution is probably in good condition. 

4. Add the contents of the test tube that contains the boiled peas to 
the test tube of Fehling's solution. 

Note : Keep the flame near the upper surface of the boiling mixture. 
If grape sugar is present in sufficient amount, a yellow color will de- 
velop in the mixture. 

5. Repeat the experiment, using sweet corn, dent corn, beans, and 
any other seeds you may have. 

6. Make out a list of these and write down in the order of sugar 
found. 



84 



TEST FOR FOODSTUFFS IN SEEDS AND FRUITS 85 

Test for Starch 

Materials : Iodine solution, test tubes, mortar and pestle, 
gas or alcohol lamp. 
Experiment : 

1. Crush five or six peas. 

2. Boil in a test tube with water for five minutes. 

3. Pour a few drops of this solution into a test tube, add water to 
make up to 10 cc. 

4. Add a few drops of solution of iodine and boil. 

5. The development of a blue color indicates starch. 

6. Now use three or four times the quantity of solution used in (3). 
Add same amount of water. Add solution of iodine and boil. How 
does the blue color now compare in intensity with that obtained before ? 
What do you conclude ? 

7. Repeat the experiment, using beans, corn, wheat, potatoes, etc. 

Test for Protein 

Materials : Strong nitric acid (c.p.), strong ammonia water 
(ammonium hydroxide). 
Experiment : 

1. Crush five or six peas. 

2. Boil in test tube with 10 cc. of water. Cool by holding test tube 
in cold water. 

3. Wipe off the water from the test tube. Add a few drops of nitric 
acid. Boil and again cool. If a yellow color develops, protein is indi- 
cated. 

4. Add a few drops of ammonia water. If the yellow color deepens 
to orange, you have a further indication of protein. 

5. Repeat the experiment, using beans, corn, wheat, and other seeds 
available. 



86 PLANT BIOLOGY 

Test for Oil 

Materials: Walnut meats, sunflower seeds, brazil nuts, 
coconut, etc. 
Experiment : 

1. Crush walnut meats or sunflower seeds and put into a test tube. 
Add ether or benzine until test tube is two thirds full. Shake well. 
Let stand a few moments and shake again. 

2. Filter and evaporate the filtrate ; that is, the part that leaks 
through the paper. 

3. Rub this substance that does not evaporate on writing paper and 
see if you get a translucent grease spot. A grease spot can be recognized 
in general by its appearance. This is not a very satisfactory test, but 
it is one that is usually accepted. There are complicated chemical tests 
for oil which are more accurate. 

4. Repeat the experiment, using brazil nuts, coconut, whole-wheat 
flour, castor beans, or other seeds that may be available. 



86 



TO TEST SEEDS FOR GERMINATING QUALITIES 

Corn Test 

Materials : Moss, sawdust or blotters or seed-testing frame. 
Experiment : 

1. Get some ears of seed corn and select six kernels from each ear as 
follows : two kernels from opposite sides near the top of the ear, two ker- 
nels from the middle, and two from the bottom. 

2. Soak the kernels for two hours in water and place them in moss 
or blotters or seed-testing frame. Keep the kernels from the same ear 
in a group. Keep these kernels where it is warm and moist. If kept 
too cool or too moist, the kernels will rot. 

3. After five or six days examine the corn and count the number 
that have germinated. 

4. Repeat this experiment, using beans, peas, carrots, parsnips, and 
other seeds that are to be planted the following spring. 



TEST FOR VIABILITY OF SEEDS 

Directions: Get some old seeds from home or from the 
store and find out as near as possible the age. Test in the 
same way as for corn, except that you may use ten or fifteen 
seeds of each kind. Use seeds of different kinds but of the 
same age for each experiment. The purpose of this experi- 
ment is to find what kind of seeds will grow after being 
kept two, three, four, or five years. 

Fill out the following outline after having experimented 
on various kinds of old seeds. 



Kind 


1 Yr. 


2 Yr. 


3 Yr. 


4 Yr. 


Beans 










Peas 










etc. 





















ss 



TO STUDY CONDITIONS NECESSARY FOR 

GERMINATION 

A. Moisture 

1. Soak a handful of peas in water over night. 

2. Take three cups or tumblers and place a piece of blotting paper 
in the bottom of each. 

3. Place ten soaked peas in each tumbler. Half fill one tumbler 
with water, sprinkle a little water on second bottle. Keep third dry. 
Cover each tumbler with a loose piece of cardboard. 

4. Examine each day for ten days. Fill out the following report on 
the sixth, eighth, and tenth days : 





6th Day 
How Many Grew 


8th Day 
How Many Grew 


10th Day 
How Many Grew 


Peas covered with 
water 








Moist peas 








Dry peas 









5. What can you say about the moisture condition necessary for 
germination ? 



89 



90 



PLANT BIOLOGY 



B. Temperature 

1. Soak a handful of peas in water over night. 

2. Take three tumblers and put a piece of moist blotting paper in 
the bottom of each. 

3. Into each put ten soaked peas and keep the moisture condition 
favorable for germination. 

4. Now put one tumbler where it is hot, say near the heat source 
such as the radiator, register or stove. Put the second out on the win- 
dow ledge or some other cold place. Put the third where the temperature 
will be about 70 degrees all the time. Put the same amount of water in 
each. 

Note : An ideal place for germinating seeds would be an incubator 
where a temperature of 70 degrees could be constantly maintained. 
Such incubators are used in experimental stations where accuracy in 
observing germinating qualities is of great importance. 



5. Fill out the following report : 




Ear 


Number Grown 


Weak Growth 


Stkong Growth 


No. 1 








2 




k 




3 








4 









C. Oxygen 

1. Put forty or fifty soaked peas in a wide-mouthed bottle. 

2. Tip the bottle on one side and fill above and around peafl with 
moist sand. Completely fill bottle and then seal with paraffin or sealing 
wax. 



CONDITIONS NECESSARY FOR GERMINATION 91 

3. Now take same number of soaked peas and fill bottle half full 
of moist sand. Do not seal. 

4. Let both bottles have same treatment otherwise, such as same 
heat and moisture. 

5. Fill out the following report : 





Number 
Sprouted 


Strong 
Growth 


Weak 
Growth 


Few 
Spoiled 


Many 
Spoiled 


Peas with sand and 
sealed 












Peas with less sand 
not sealed 













To Test Germinating Seeds for C0 2 

1. Place in a bottle a handful of germinating peas. 

2. Replace the stopper and after three days or so remove some of 
the air above the peas with a rubber bulb and glass tube. 

3. Force this air through lime water. Do this three or four times. 

4. What happens in the lime water? 

Note : C0 2 forms a milky substance in lime water. 

5. Hold a lighted stick in the bottle with the germinating peas. 
Does it burn less brightly ? Does it go out ? 

Note : Oxygen is necessary to keep the stick burning. "What is indi- 
cated from your observations with the lighted stick? 

6. Breathe through a tube into lime water. Do you get a milky color 
in the lime water ? What does this indicate ? 

7. Do germinating seeds give off C0 2 ? Does the human breath con- 
tain C0 2 ? 



ROOTS 

The Carrot 

1. Cut a carrot in longitudional sections. Make out a central ar 
known as the central cylinder ; outside of this a thicker area, the con 
and surrounding it all the epidermis, the covering. 

2. Make a sketch to show these regions. Label. 



3. Make a cross-section of a carrot and identify the same regions. 

4. Make a sketch to show these regions. Label. 



5. Secondary roots may appear in these sections. To which region 
are they connected? Show this in your drawing. 

6. Stand a cut end of the carrot in red ink for a few hours. Through 
which region does the ink rise? 

7. Make a similar study of parsnip, beet, vegetable oyster or other 
roots. 

The Onion Root 

1. Select strong roots of growing onions and examine the natural 
ends. These are blunt and usually show the root-cap. Make thin, lon- 

92 



ROOTS 93 

gitudinal sections through these ends and stain with methylene blue. 
Make out central cylinder, cortex, and epidermis. At the free end of the 
root should be found a cluster of cells known as the root-cap. Just back 
of the root-cap near the outer end of the central cylinder should be found 
a group of small cells, the growing region known as the meristem, 

2. Make a sketch of longitudinal section of onion root to show 
central cylinder, cortex, epidermis, root-cap, and meristem. 



Wheat Kernels 

1. Place several kernels of wheat on moist blotting paper or cotton 
and invert a glass tumbler over them. After a few days the hypocotyl 
and roots should form. If the moisture condition in the tumbler is 
favorable, the roots will be covered with fine root hairs. 

2. Make a sketch to show the roots, root hairs, and hypocotyl. 



3. From a prepared slide showing cross-section of one of these roots, 
determine how the root hairs are formed and from what they are out- 
growths. 

4. Make a sketch to show this cross-section and label central cyl- 
inder, cortex, epidermis, and root hairs. 



5. If the prepared slide is well stained and a careful examination 
made of the root hairs, the nuclei of the root hairs can be seen. Where 
are they located in relation to the epidermis? 



94 PLANT BIOLOGY 

Corn 

1. Examine growing corn and look for roots that start above the 
ground and reach to the ground on all sides. These are brace roots. 
How is their development an advantage to the growing corn ? 



2. Make a sketch to show these brace roots in relation to the corn 
stem and the surrounding ground. Do they develop strong roots 
branching at their lower end? 



Fibrous Roots 

1. The carrot and parsnip are examples of tap roots. Some plants 
have fibrous roots. Select from the garden or lawn those weeds that do 
not have tap roots but have a branching system of small roots. 



2. Make a sketch of one that shows a good distribution of roots and 
compare this root surface with the part of the plant above the ground. 



3. Make a list of common weeds that you have gathered which show 
fibrous roots. 



Fascicled Roots 

1. The dahlia is a good example of a plant with fascicled roots. 
These roots are thickened and shortened for food storage. 



ROOTS 95 

2. Make a sketch to show a cluster of these roots. They serve as a 
means of propagation. 



Atrial Roots 

1. The Boston ivy has aerial roots growing along the stem. 
These roots penetrate tree trunks, brick walls, etc., and serve as hold- 
fasts. 



2. Make a sketch to show a portion of a stem with these roots 
attached. 



STEMS 

Spring or Late Fall 
The Horse-Chestnut Stem 

1. Examine the stems with strong buds. 

2. Notice the large terminal hud. 

3. What purpose does the gummy part of the bud serve? 

4. What is the arrangement of the lateral buds in reference to each 
other ? 

5. Notice several pairs'of adjacent buds. How are these pairs 

arranged in. reference to each other? 

6. Directly beneath the bud are the leaf scars where the leaves of 

other years have been attached. 

7. Inside the leaf scar nol ice the row of small projections. These are 
bundle scars. Count them. How does the Dumber compare in different 
leaf scars? How do these numbers compare with the number of leaflets 

of the compound leaves of the horse-chestnut'.' 

8. Notice the small scars that encircle the stem al intervals. Th< 

are bud scale scars. They arc formed by the bud scales of earlier ye 

9. What does the space between the bud scale -car- represent '.' 1 te- 
termine the age of the oldest growth in your specimen. 



96 



STEMS 97 

10. Notice the small points or marks on the bark of the new growth. 
These are lenticels. They connect with the inner portion of the stem. 
How may the stems get oxygen for respiration during the season the 
leaves are not functioning? 

11. Notice the scars at the union of some lateral stems with the main 
stem or on the shoulders of the main stem. These are not numerous and 
you may have to examine several stems before you find one. They 
are the flower cluster scars and mark the place where the flower cluster 
was joined to the stem. Later the fruit was nourished through the same 
region. Why are they not numerous in comparison with leaf scars? 

12. Examine the pith exposed by cutting the stem diagonally. 
Notice the layers of wood and bark outside the pith. 

13. Make a sketch of a typical horse-chestnut stem, showing 
terminal and lateral buds, leaf scars, bundle scars, bud scale scars, year 
growths, lenticels, flower cluster scars, and the pith with surrounding 
layers of wood and bark. 



Cross-section of a Woody Stem 
Horse-chestnut 

1. Compare the pith, the wood, and the bark. Which is firmer? 

2. Examine a cross-section of an older stem of horse-chestnut. How 
does the size of the pith compare with the younger specimen? 

3. Have you any reason to believe that the growing wood crowds 
up the pith? 



98 PLANT BIOLOGY 

4. Notice radiating lines running through the wood. These are 
medullary rays. They serve to convey materials from the pith to the 
outer layers. 

5. Notice the concentric ring about the pith. Compare the number 
of these rings in the young stem with those in the old stem. These are 
rings of annual growth. 

6. Notice the ends of tubes in the woody section. These carry 
materials from the root to the leaves and from the leaves to the root. 

7. Pare off strips of the bark. Can you find strengthening fibers 
running up and down the stem ? These are bast threads. 

8. Examining the cross-section of the stem, tell which part gives it 
support ? 

9. Is there any relation between the hollow cylinder of wood and 
a solid cylinder of the same weight? Which is stronger? Would the 
horse-chestnut stem be stronger if the same amount of wood were 
arranged in a solid cylinder or in a hollow cylinder ? 

10. Take a horse-chestnut stem two or three inches long and place 
a cut end in red ink. Let it stand two or three hours and then make 
cross-sections, beginning with the upper end of the stem. In what 
portion of the stem do you find that the ced ink has risen most ? Try 
grape stems, elder, parsnip, carrot, etc. 

11. Which ones seem to carry the ink highest in the same time? 

12. What part of the stem, then, seems to carry fluids up? 

13. Take several willow stems and put them in water until they root. 
After they have established good, long roots, cut a ring one half inch 
wide around the stem and remove the bark. Scrape the wood beneath 
the bark to be sure all of the bark is removed. Replace in the water 



STEMS 99 

with the cut portion underneath the surface of the water. Observe for 
two or three weeks. What happens to the roots that were started 
earlier? What happens at the upper cut edge? Account for what 
happens. 



Stems in Their Relation to Life 

1. Take a plant such as a geranium or any house plant and place 
it in a window. Do the stems respond to the light ? How ? 

2. Turn the plant halfway around. Leave for a few days. Have 
the stems changed position? How? What is the effect of light on 
stems ? 



3. Place some growing seedlings in the dark. Place some of the 
same age in a good light. Keep moisture and temperature conditions 
the same. After a week or ten days, compare the growth made under 
the two different conditions. What is the effect of darkness on the grow- 
ing seedlings? 

4. Does darkness stimulate growth ? If a stem is unevenly lighted, 
that is, one side well lighted and the other poorly lighted, would this in- 
equality explain why plants lean toward a window? 

5. Sometimes a barrel is put over pie plant early in the spring. If 
the barrel is tight so that the interior is dark, what effect should this 
have on the growth of the pie plant? Why? 

6. Potatoes left in the cellar or other dark place during the early 
summer will grow sprouts ten or twelve feet long. Is this in accord- 
ance with the action of other stems when grown in the dark ? 

7. What adaptation is shown here which would apply to buried stems 
or seeds planted too deeply? What does the stem gain naturally by 
having its growth stimulated by darkness? 



100 PLANT BIOLOGY 

Sunflower Stem 

1. Cut very thin slices of a small sunflower Btem in cross-section. 
Stain with methylene blue and examine with a low-power microscope. 

2. Notice the row of bundles that extend around the Btem just in- 
side the bark. These are fibro-vascular bundle They afford st rength 
and also carry solutions. These bundles have three regions. The outer 
region is phloem and is the bark part. Next inside is the cambium region 
or growing region. Next inside is the xylem or the woody part of the 
bundle. 

3. Make a sketch to show the arrangement of these bundles in re- 
lation to the whole stem and also roughly to show the general form. 



4. Use a higher-power lens and make a sketch to show more in de- 
tail the appearance of a single fibro-vascular bundle. Label pith, xylem. 

cambium, phloem. 



5. Review the make-up of these various regions and the other 
details of bundle structure in your text. 

Corn Stem 

1. Cut thin slices of a moderate-sized corn stem in or ctkm. 

Stain with methylene blue and examine with :i lower-power lens. 



STEMS 101 

2. Find the areas scattered through the stem that are more deeply 
stained. These are the fibro-vascular bundles of the corn stem. Com- 
pare their arrangement with that of the sunflower bundles. 

3. Examine with a higher power lens a single bundle and notice the 
arrangement of parts in comparison with the bundle of the sunflower 
stem. Surrounding the whole bundle are thick-walled cells known as 
the bundle sheath. Notice extra large openings inside the bundle. 
These are special conducting tubes. Notice thick-walled cells at the ends 
of the bundle. These are strengthening cells. Notice the other cells 
and by reference to your text determine the functions of the different 
kinds. 

4. Make a sketch to show the arrangement of bundles in a corn 
stem, and also, by aid of a lens, a sketch to show the regions of a single 
bundle. Label to show pith, bundle sheath, woody cells, and conducting 
cells. 



MODIFIED STEMS 
The Potato 

1. The potato is a modified stem for food storage. It has most of 
the features of an ordinary stem. 

2. Select clean, white potatoes and notice the eyes. These c 
are buds. Below the eyes are small scales which may be considered 
dwarf leaves. The buds are, then, located in the axils of the leaves. 
Is this as it should be? 

3. Notice the small projections on the surface of the potato. These 
are lenticels. 

4. Make a cross-section of a potato and find the thickened areas that 
correspond to fibro-vascular bundles. These are poorly developed in 
the potato for the reason that the potato is a storage region rather than 
a conducting region. 



5. Make a sketch to show a potato with the stem-like features 
labeled. 



The Onion 

1. The onion has a modified stem which is short and thick, sur- 
mounted by thickened leaves surrounding the buds. The roots are in a 
cluster from the lower end of the stem. In this case, the stein is reduced 
to its lowest terms while the bulk of the onion is thickened leaves and 
buds. 



102 



MODIFIED STEMS 103 

2. Make a sketch to show the appearance of an onion in cross-section. 
Label to show bud region (in some cases there will be two or more buds) 
and thickened leaves. 



3. Make a sketch to show an onion in longitudinal section. Label 
to show thickened leaves, bud, stem, roots. 



The Cabbage 

1. The cabbage has a short, thick stem with thickened leaves closely 
set with buds in their axils. 



2. Make a sketch to show a cabbage in longitudinal section, labeling 
stem, thickened leaves, and buds. 



Othek Stems 

1. Stems are usually for support, for food storage, or to give the 
leaves favorable positions in the sunlight. Some stems are modified 
into thorns, as in the case of wild apple, honey locust, prickly ash, etc. 

2. Select small branches of honey locust or wild apple and examine 
them to find out the form and arrangement of the thorns. Make 
a sketch to show the arrangement of the thorns and buds. 



104 PLANT BIOLOGY 

3. Do these thorns serve any useful purpose? It is sometimes 
said that thorns protect stems from being eaten. Does this seem a 
good explanation to you? 

4. Quack grass has underground stems by means of which the grass 
extends its area and is a means of propagation. Select some quack grass 
with these underground stems carefully preserved. Make a sketch to 
show how these grow and the buds they form. 



5. What other plants have underground stems? Do they serve 
the same purpose as in quack grass? 

6. Examine runners of strawberries and notice how these stems 
likewise serve to extend the area of the plant. Examine some runners 
of strawberries and find out how many small plants may form on one 
runner. 

7. Make a list of edible stems, including such stems as are found 
in stores or in neighboring gardens. Such stems are modified for food 
storage. 

8. Make a list of stems that serve as means of propagation. 

9. What is layering ? Grafting? Budding? Slipping? 



10. How are grapes propagated? Currants? Blackberries? 
Raspberries ? 



LEAVES 

General Characters 

1. Gather the leaves of twelve or fifteen kinds of trees. Examine 
them and note as many points of resemblance as you can find. These 
resemblances may include color, thickness, veining, petioles, and other 
resemblances. 

2. In how many ways do they differ ? These differences may include 
size, hairiness, margins, form, and such other differences as you may 
find. 

3. Write a description of your observations summarizing the re- 
semblances and differences of leaves. 



The Maple Leaf 

1. Select a wild form of maple leaf and make a sketch to show the 
whole leaf. Trace the outline if time does not permit of a free drawing. 



2. Label petiole (the part that attaches the leaf-blade to the stem), 
midrib, and other prominent veins and leaf-blade. 



105 



106 PLANT BIOLOGY 

3. Hold the leaf up to the light and notice the many fine branches of 
the larger vein. 

4. Use hand lens to see the still smaller veins. 

5. What is the function of the leaf? 

6. What are the functions of the veins? 

Leaf Forms 

1. Gather leaves of elm, oak, lilac, horse-chestnut, and ash. 

2. Make a sketch to show outline and venation (veining) of elm, 
oak, and lilac. The elm has a toothed margin, the oak a lobed margin, 
and the lilac has an entire margin. Label these leaves toothed, lobed, 
entire, respectively. 



3. Compare the prominence of veins in each and notice how the 
lateral veins join the midrib. Show these characteristics in your draw- 
ings. 



4. In what way is a river system suggestive of the system of veins 
in these leaves? 



5. What relation do these veins have to the fibro-vascular bundles 
of the stem? 



6. What advantage does a flat leaf derive from having its leave- 
broad and thin? 



LEAVES 107 

7. Make a sketch to show the compound leaves of horse-chestnut 
and ash. 



8. How many leaflets in the horse-chestnut leaf have you sketched ? 

9. Count them in other leaves. Is the number always the same? 

10. How do the numbers of leaflets compare in general with the number 
of bundle scars in the leaf scars of the horse-chestnut stem? What do 
you conclude ? 

11. How many leaflets in the ash leaf? Does this number vary in 
different ash leaves ? Is there any relation between bundle scars of the 
ash leaf scar and the number of leaflets of the ash ? 

12. Does the midrib of the elm leaf divide it into two equal parts? 

13. If you are uncertain about the elm leaf, fold it on the midrib. 

14. Compare the oak and lilac with the elm leaf in this respect. 

15. Which of these leaves has the most uneven sides? 

Functions of Leaves 
Respiration 

1. Take some algae or other water plants that grow entirely in the 
water and place in a large glass jar. Place a funnel inverted in the jar 
and over the plants. Fill the jar with water so that the level of the water 
is above the opening of the funnel. Over the open end of the funnel in- 
vert a large test tube filled with water. 



108 PLANT BIOLOGY 

2. The purpose of this apparatus is to catch any gas given off by 
the plant that is not readily soluble in water. 

3. Keep the apparatus in the dark or in a poorly lighted part of the 
room. Do you observe any gas collecting in the test tube? 

4. Place the apparatus in the strong sunlight. Do you observe any 
gas bubbling up in the test tube? 

5. If the plants are too densely crowded or are not numerous enough, 
you may have to repeat the experiment for a good result. 

6. In case you get a quantity of gas, you may remove the test tube 
and quickly thrust in a glowing match. 

7. In the presence of oxygen, the glowing match will burst into 
flame. 

8. What happened in your case? What do you conclude? 

9. If leaves give off oxygen, is it associated with respiration or photo- 
synthesis ? 

10. Is the giving off of oxygen limited to water plants ? What about 
the plants in the garden and woods? 

11. Do plants give off carbonic acid gas (C0 2 )? 

12. Is carbonic acid gas soluble in water? What makes soda water 
bubble? 

13. If carbonic acid gas is soluble in water, could this apparatus 
just used collect carbonic acid gas'.' 



LEAVES 109 



Transpiration 

1. Take a small geranium plant or any other strong plant that is 
growing in a crock. Cover the crock with a cardboard and seal the open- 
ing around the plant and the split in the cardboard with modeling clay 
or gum. The idea is to prevent the water vapor from the crock getting 
above the cardboard. 

2. Invert a glass jar over the plant and seal the lower edges with 
modeling clay or gum. 

3. Place the plant just covered in the sunlight, preferably where a 
good breeze may strike it. 

4. After a time the inside of the glass jar should show a change in 
appearance. 

5. Account for any change that you see. 

6. Transpiration in plants is the giving off of moisture through leaf 
tissue. 

7. Why do plants need water? 

8. How are plant foods from the soil, roots, and stems brought to the 
leaves? Consider this in relation to root hairs, fibro- vascular bundles, 
and veins. 

9. If the leaves were obliged to retain all water brought to them by 
the veins, what would be the effect on the weight of the leaves? Their 
size? Their functioning? 

Evaporation through Leaf Tissues 

1. Take two large, thick leaves of even weight. If you cannot find 
two of the same weight, get two of nearly even weight and balance with 



110 PLANT BIOLOGY 

dry sand or small weights. Dip the cut ends of the petiole in melted 
paraffin. 

2. The thicker and larger the leaves, the better results your experi- 
ment will give. 

3. Cover the upper side of one leaf with butter or vaseline and 
cover the lower side of the other in the same way. Take rare to keep 
one side absolutely free from oil. Put the leaves again on the scales 
and balance. 

4. Place the scales in strong sunlight with the lower surface of each 
uppermost. 

• 5. Do you find that they soon get out of balance? Which leaf is 
heavier? 

6. Which surface evaporates the water faster, upper or lower? 

7. Transpiration takes place more, — from which surface? 

8. What advantage does the leaf derive in having the surfaces as you 
find them? 

9. Some leaves do not have a normal upper and lower surface, as in 
the case of the onion. 

10. Strip small shreds of epidermis from fresh leaves of growing 
onions. Mount in water and examine with a f objective. 

11. Do you find small pores or openings ? These are stomata small 
openings each surrounded by two guard cells. These guard cells reg- 
ulate the size of the stomata and so control in a measure transpiration. 



LEAVES 111 

12. If possible, study a prepared slide showing these guard cells, 
stomata and epidermal cells of onion or other plant. 

Leaves as Food Storage 

Is Make a collection of all the different leaves that are used as 
food, such as celery, cabbage, spinach, lettuce, chard, endive, etc. 

2. Compare these as to color. Which ones are green? Which 
are bleached or yellowish white? 

3. How is celery bleached? What is the difference in appearance 
bleached and unbleached celery? 

4. What change in taste when celery is bleached? 

5. What gives leaves their bitter taste? What develops chloro- 
phyll in leaves ? 

6. What plants do you know that lack green color? 

7. What is the color of the cabbage leaf in the head near the stem? 

8. Are cabbage leaves bitter ? 

9. What difference is there in the process of bleaching cabbage 
leaves and celery? 

10. Why are spinach leaves used as food? Are they bleached? 

11. Is all chlorophyll equally bitter? 

12. Are very thin leaves, such as lettuce and spinach, as bitter as the 
heavy thick leaves of unbleached celery? Why? 



112 PLANT BIOLOGY 

13. In which of the above-named leaves is the petiole the principal 
food? In which the leaf blade? 

14. Boil some of the spinach leaves in alcohol. Is chlorophyll soluble 
in alcohol? 

Note : In boiling alcohol use a deep dish and a low flame and do not 
boil too fast. Why? 



Modified Leaves 

1. We have seen that the normal functions of leaves is in photosyn- 
thesis, transpiration, respiration, and digestion. Leaves also serve as a 
food storage region, and we are to consider other uses to which leaves 
are put. 

2. Examine the new growth of ivy, pea, grape, woodbine, and 
other plants that have tendrils. 

3. Which of these have their tendrils arranged opposite leaves or 
in the place of leaves? 

4. Examine the leaves of pitcher plant, drosera. These leaves are 
modified to capture insects. 

5. The pitcher plant leaf is, as its name indicates, in the form of a 
pitcher. Notice the colored streak on the inside of the leaf. Mosquil 
are frequently caught in the pitcher plant. Notice the bristles inside 
the leaf. Which way do they point? How could these bristles aid in 
the imprisonment of insects? 



6. Most of the leaves of the pitcher plant are erect. They thus 
hold rain water. Do you find any insects floating in the water? Would 
the decayed insects furnish food for the plant? 

7. If possible, observe the pitcher plant blOBSOm. Does this blos- 
som appeal to insects for pollination? dive reasons for your answer. 



LEAVES 113 

Are the insects that are attracted to the pitcher plant blossom entrapped 
in any way? Do the leaves and blossoms use different kinds of 
insects ? 

8. Examine barberry leaves from different shrubs. Some of these 
leaves show a variation from a large leaf with a few thorns down to 
a very small leaf with large thorns to a condition of only thorns. 

9. Leaves as hold-fasts. We have already seen that some leaves are 
replaced by tendrils. Other leaves keep their leaf -like shape while their 
petioles serve as hold-fasts. Examine petioles of nasturtium and clem- 
atis. Can you find other leaves in which the petioles are holding the 
plant erect? 

10. Examine the new growth of common locust and compare it with 
the year-old stems. Select the common locusts that show common 
appearance. What relation do these thorns have to the leaf in the 
new growth ? What relation do they have to the leaf scar in the old 
growth? These thorns are the modified stipules of the leaf. 

1 1 . We have thus seen that the leaf blade may be modified for various 
purposes as in food storage, tendrils, insect traps. The petioles may be 
modified into hold-fasts as in nasturtiums and clematis, and the stipules 
into thorns as in the case of common locust. 

12. Examine in the field, if possible, the drosera leaves during favor- 
able weather. Some of these leaves will be found open and others will 
have their toothed edges closed holding an insect. These leaves are 
special adaptations for catching insects. In case it is impracticable to 
make a field trip, a very good idea of the action of these leaves may be 
gained from pictures and drawings in addition to the descriptive matter. 

Digestion 

1. Select a strong growing plant and fasten two pieces of black paper 
on opposite sides of a part of the leaf. Place the plant in the sunlight. 
After five or six hours cut off the leaf and remove the black paper. 



114 PLANT BIOLOGY 

2. Place the leaf in boiling water to remove the chlorophyll. 

3. Test the leaf for starch by boiling in a solution of iodine. 

4. Which part shows a blue color? 

5. Account for the fact that not all the leaf develops a blue color. 
What has become of the starch that must have been under the black 
paper earlier? 

6. Account for the fact that potatoes grown in the shade of a build- 
ing will not do so well as out in full sunlight. 

7. Where is the starch made that forms the large part of the potato 
tuber? 

8. What color is always associated with chlorophyll ? What is the 
relation of this color to chlorophyll? 

9. Name some plants that are not green and that cannot make starch . 

10. Name four functions of leaves. 

11. Why do plants that lose their foliage fail to bear fruit? 

12. Suppose the leaves of a potato plant were picked off early in the 
season. How could this affect the tubers? 

13. What is the effect if potato beetles eat a large part of the foliage 
of potato vines? 

14. If tent caterpillars eat the foliage of apple trees, how will this affect 
the apple crop? 



LEAVES 115 

15. What is the effect on the peach crop when the leaves turn yellow 
or have leaf curl? 

16. Why should the state and national governments maintain ex- 
perimental stations to study diseases of plants and animals? 

17. What is the effect on the price when there is a big crop of food- 
stuffs? 

18. How does this affect all the people? 



FIELD TRIP 

Adaptations of Plants That Serve as Protection 

1. Take a field trip to a pasture lot and study the plant- that the 
cattle have not cropped. 

2. Make a list of them and try to explain why they are uneaten. 
Some plants have thorns or prickers, some are bitter, sour, pungent, or 
otherwise distasteful. Some are poisonous, some are very hairy, and 
some are too dry and leathery. Many of the plants have objectionable 
odors. 

3. What other objectionable features can you find from your stand- 
point ? 

4. This list may be inaccurate because we assume that cattle like 
and dislike in the same way we do. Cattle have preferences in their food 
taste and if they can get all the good grass they want, they may not cat 
certain plants. If the grass dries up, or if the cattle are too crowded on 
pasture, they may eat some of the plants that seem objectionable to us. 

5. Several field trips will show that at different times cattle will 
have different tastes for plants. 

G. Another point we should bo careful about is this: avoid Baying 
a plant is poisonous and therefore it will not be eaten. A better way to 
say it is, that a plant is poisonous and cattle have come to recognize it 
as such and have learned not to eat it. We should be careful about giv- 
ing reasons for plants being thorny, bitter, sour, sweet, fuzzy, or poison- 
ous. 



110 



FIELD TRIP 111 

7. Thus we should not say that all of these are bitter and hence 
animals will not eat them, because some animals eat plants for the 
bitter taste, and we also know now that a bitter taste is always asso- 
ciated with chlorophyll. We also know that plants must have chloro- 
phyll in order to make starch. So that the real reason that plants 
are bitter is because chlorophyll is bitter. 



ALGAE, FOR EXAMPLE, SPIROGYRA 

1. Gather the green pond scum from watering troughs or Btanding 
water and place a portion of it under :i low-power microscope. 

Note: Not all such pond scum is spirogyra, for there arc many 
species of algae which arc green. 

2. Examine your specimen for spiral bands of green running through 
the tubes. Are these spirals marked off into cells ? 

3. What color are these spyra bands? What is suggested by this 
color? Are these threads attached to roots or branches'.' Arc they 
independent ? 

4. How are these plants able to live without a root Bystem or with- 
out leaves? Are these threads more like leaves or stem? Give a rea 

for vour answer. 



5. From a prepared slide or chart, study conjugation. Can you find 
outgrowths from adjoining stems? Can you finds tube connecting ad- 
joining stems? 

6. Can you find zygospores? Compare the formation of a syg 
spore of the spirogyra and the bread mold or any other mold afl 
to position, shape, color. 

7. The formation of zygospores in spirogyra Berves the same purp 

as in mold. What is it? How is this process an adapt at ion - ; 

8. Some algae have archegonia and antheridia and reproduce sex- 
ually. Is spirogyra sexual or asexual? Is the zygospore produ 
by sperms and eg^s? How is it produced? 

lis 



BACTERIA 

Note ', Bacteria are small fungus plants that are either parasites or 
saprophytes. They are widely distributed, and air and dust contain 
large numbers. Certain substances, known as media, are prepared from 
meat juices, gelatin, and sugars, which afford favorable growing places 
for bacteria. One of these media is prepared from agar, which is a gela- 
tin-like substance obtained from plants. Agar media may be made from 
a formula or purchased in test tubes from supply houses. When this 
agar is melted in boiling water and poured in plates, we have a growing- 
place for bacteria. 



1. Place four test tubes of agar in a vessel containing water and bring 
to a boil. 



2. Take a few drops of tap water or a drop of milk and place in a 
petri dish. 

3. Cool the boiling water that contains the test tubes of agar to a 
temperature that is comfortable to the hand. Shake the water around 
the test tubes until the agar has been cooled to the same degree. 

4. Pour the partly cooled agar into the petri dish and replace the 
cover. Give the petri dish a slightly whirling motion to mix the agar 
with the drops of water in the dish. Allow this to stand for three or four 
days at room temperatures. 

■ 

5. Hold the petri dish up to the light and count the spots that have 
formed on the agar. These are colonies of bacteria. Each colony has 
grown from a single bacterium. The number of colonies will indicate 

119 



120 PLANT BIOLOGY 

the number of bacteria that you placed in the petri dish that are nour- 
ished by this agar medium. 

6. This method of counting bacteria is used in determining the b 
teria in milk or water. If the colonics are too numerous to count, then 

the experiment should be repeated by diluting. For example, if 1 
of milk is placed in 100 cc. of sterile water, and then 1 cc. of the dilution 
is taken, the total number of bacteria in 1 cc. of milk can be determined 
by multiplying the number of colonies on the petri dish by 100. 

7. Notice that the shape and color of the colonies vary. Some I 
elliptical, some are round, and some are uneven. Some are gray, some 
are white, some are yellow. What other shapes and colors can you 
find? 



A FUNGUS, FOR EXAMPLE, BREAD MOLD 

1. Take pieces of moist bread -and keep them in a loosely covered tin 
box for a few days or until the familiar bread mold appears. " 

2. Describe the general color. 

3. Is there any evidence of chlorophyll? What do you conclude? 

4. Plants that lack chlorophyll are unable to lead an independent 
life. Such plants are either parasites or saprophytes. Parasites are 
found on living forms and saprophytes on lifeless forms. Is the bread 
mold a parasite or saprophyte ? 

5. Examine with a hand lens the mass of bread mold. Can you find 
dark spots on the ends of white stalks? Sporangia are born on the 
ends of white stalks and contain spores. When these sporangia break, 
the spores are scattered and are widely distributed. They develop 
into bread mold when the conditions of growth become favorable. 

6. Study from prepared slides or charts the structure of the mold 
mass (mycelium) and the sporangia. Do you find any evidence of cell 
structure in the mycelium? 

7. From a prepared slide or chart study the conjugation of bread 
mold. The joining threads of the mycelium under certain adverse con- 
ditions send out projections which meet and form a zygospore. This 
spore is resistant to a high degree. It is a means of reproduction and is 
an adaptation to carry the mold through unfavorable conditions. 

8. Some spores are not killed by prolonged boiling in water. 

121 



THE MOSS 

1. Gather specimens of moss that have the long, reddish stems grow- 
ing from the top surmounted with capsules. 

2. Separate several plants from the cluster and notice the short, 
leafy stems at the lower part, poorly developed root system, and the 
slender stem with the capsule growing out of the top of the leafy 
stem. 

3. This plant represents both generations (sexual and asexual). 
The lower leafy part is the gametophyte, and the upper slender part, 
the sporophyte. 

4. Make a sketch to show both generations of moss. Label. 



5. Compare the moss and the fern as to the relation of the game- 
tophyte and the sporophyte. 

6. Which is the conspicuous generation in the fern, sporophyte 

or gametophyte ? 

7. Which is the conspicuous generation in the moss, sporophyte Of 

gametophyte ? 

122 



THE MOSS 123 

8. Examine the capsule at the top of the sporophyte with a low- 
power microscope. Can you find the opening at the top through which 
the spores emerge? Can you find the tooth-like projections (peristome) 
at the upper part of the capsule ? 

9. From a prepared slide or from a chart study sections through the 
top of the gametophyte tmd compare archegonia of moss and fern. Com- 
pare antheridia of moss and fern. Compare spores of moss and fern. 

10. On the prothallus of the fern we find both archegonia and anther- 
idia. How is it in the moss? 

11. Study the development of the moss spore from a prepared slide 
or chart and compare it with the thread-like algae (spirogyra). 



THE LOWER PLANTS 

The Fern 

1. Gather some fronds (leaves) of ferns. Examine the plant for 
~oots and stems. Is there a good root system? Are the stems woody ? 
Are the fronds green ? Can they make starch ? 

2. Examine the underside of some of the fronds for little brown 
spots. These are clusters of spore cases (sori). 

3. Examine some of the sori under a low-power microscope. Notice 
the spore cases (sporangia) that hold the spores. 

4. Examine the spores under a low-power microscope. Are the 
surfaces smooth or rough? 

5. Under favorable conditions of temperature and moisture, the 
spores will grow into small flat plants called prothallia (the gametophy 

6. If possible examine a prepared slide showing tin 1 underside of the 
prothalium. Look for spherical bodies (antheridia) and bottle-sha; 
bodies (archegonia). These antheridia produoe sperm cells and the 
archegonia produce the eggs. 

7. When a sperm cell, which is motile, reaches the egg in the arche- 
gonium, fertilization takes place, and a new plant (sporoph} 

which lives for a time on the prothalia (the gametophyti 

8. The little plant (sporophyte) is later to grow into the same kind 
of plant we started with having fronds, steins, and roots. 



124 



THE LOWER PLANTS 125 

9. Examine the place where ferns grow in abundance, either out of 
doors or in a greenhouse, for the prothaUia and also look for the little 
off shoots (sporophytes) that are growing from the prothallium. 

10. Notice that we have in the life history of a fern a sexual generation 
(prothaUium) and an asexual generation (sporophyte) . 

11. Alternation of generation, is illustrated in the life history of the 
fern. We have first a sexual generation that is inconspicuous. It is 
followed by an asexual generation, and these continue to alternate 
during the life of the species. 

12. From a prepared slide sketch the prothallium showing cell struc- 
ture, antheridia, archegonia, and the rhizoids (root-like structures). 

13. Sketch a portion of a frond showing sori and spore cases. 



14. Sketch a spore case (sporangium) with spores. 



HUMAN BIOLOGY 
ADAPTATION OF THE HUMAN HAND 

1. Examine your hand. Notice the joints of the finger.-. How 
many are there ? 

2. Grasp your wrist with one hand. What advantage is there in 
having the thumb larger than any of the fingers ? 

3. Hold firmly on to your wrist with one hand and try to pull your 
hand from your clenched thumb and fingers. Push hard against your 
fingers. Push hard against your thumb. Is your thumb aa si rong as the 
four fingers? 

4. What advantage is derived from having the fingers with so many 
joints? Turn the pages of this book and watch the motion of your fingen 
as you do so. How do you turn over the pages ? How do you hold the 
book with the other hand as you turn over the pap Do the joints 
in the fingers play a large part in this? 

5. Place on the table small bits of paper, pins, and other tiny 
articles. Pick them up and put them in your hand. What device of 
the fingers enables you to do this? 

6. Clench your fists. How is the clenched fist an organ of defem 
What other adaptation has the hand? How many uses can you 
name for the hand ? 



126 



THE HEAD 

1. What advantage is there in the shape of the head? 

2. What advantage in having the e} T es in the front of the head? 
Close one eye and look at an object. Close the other eye and look 
at the same object. Is there an image formed of the object in each 
eye? WTien both eyes are focused on an object at the same time 
how many objects can you see? Can you judge distance better by look- 
ing at an object with both eyes than with one eye at a time? What ad- 
vantage is there in judging a distance in case of danger? 

3. The nose is above the mouth. If odors rise, is this an advantage ? 
What danger comes from eating decayed foods? 

4. The ears are so arranged that we catch the sound most readily 
from the front. Is this an advantage? Would it be more advan- 
tageous if the ears were movable, as in the case of dogs and horses ? 

5. What advantages are there in the different forms of teeth? For 
what are the incisors or front teeth adapted? What is the use of the 
molars or back teeth? Could the incisors or molars be advantageously 
interchanged? Some flesh-eating animals have long canine teeth. 
The dog and the cat are examples. Would we be better off with long 
canine teeth like a dog? Give reasons for your answer. 

6. What advantage is there in the hair of the head? Does the head 
need special protection? The skull is thicker in front and in the back 
than at the side. Is there any advantage in this? 



127 



THE BACKBONE 

1. The backbone is made up of many individual vertebrae separated 
by pads of cartilage. What advantages do these many small bona 
give to the backbone ? What advantage is there in having pads bet \v» ten 
the vertebrae? 



2. The backbone is not straight but curves forward. What advan- 
tage is there in this shape as compared with one that is straight ? 

Note : In considering the adaptation we should bear in mind the 
position of the head with its contents and also the jar that necessarily 
comes from our methods of locomotion. 



12S 



THE FEET 

1. In most animals there is considerable resemblance between the 
front feet and the hind feet. A man has a marked difference between 
the hands and the feet. Would use account for this ? Show how. 

2. In what way are the feet adapted for walking ? For supporting 
weight? For defense? For offense? 



3. Stand up and raise yourself on your toes. Where is the muscle 
that enables you to do this? Where is the fulcrum (pivot) ? How does 
the distance from the ankle to the heel compare with the distance from 
the ankle to the toes? Suppose the distance from the ankle to the 
toes is four times the distance from the ankle to the heel, how many 
times your weight must the muscle pull to lift you up on your heels ? 

Note : There are three classes of levers. In the first class the fulcrum 
is in the middle between the weight and the power ; in the second class 
the weight is between the power and the fulcrum ; and in the third class 
the power is between the fulcrum and the weight. 



Which class of lever is the foot when lifting the body ? 



129 



DIGESTION 

Mouth Digestion 

1. Collect from the mouth ten cc. of saliva in each of three 

tubes. 

2. Into each of these test tubes put a little corn-starch paste. 
Thoroughly shake all three test tubes. Test one at once with FehUng 'i 
solution. Set the other two aside in warm water for two or three hours 
or longer. Test one of these for grape sugar. After 24 hours test the 
third for grape sugar. 

3. Account for the results that you have obtained in each of the 
three cases. 



4. From your results what is the value of thorough mastication of 
the food and the mixing of it with saliva? 

Stomach Digestion 

1. Make artificial gastric juice by taking one half gram, or 7 grains 
pepsin, 2 cc. strong hydrochloric acid, and 50 cc. of water. 

Note: Normal gastric juioe has rennin in addition, but the only 
action of the rennin is to curdle the milk. We may omit the rennin. 

2. Put 10 cc. of artificial gastric juice into each of thr> 
tubes. Label them from 1 to .'}. In No. 1 place minoed white of . 
Place No. 1 where it is as near body temperature as possible. PI 
No. 2 where it is as cold as possible without freezing. Plaee No 
in water and boil for 15 or 20 minutes. 



130 



DIGESTION 131 

3. Test No. 3 for peptone. The test for peptone is to add concentrated 
solution of caustic soda and a few drops of copper sulphate. A rose pink 
color indicates peptone. A violet color means that the white of egg 
has not been digested. What result do you get? 

4. Test No. 2 for peptone in the same way. Test No. 1 for peptone. 

5. The normal action of gastric juice is to digest protein, that is, 
change it to peptone. Protein cannot be absorbed through the walls of 
the intestines, while peptone is easily absorbed. 

6. What temperature is best for the digestion of protein, high, low, 
or medium ? 

Intestinal Digestion 

1. Make artificial pancreatic juice by mixing 10 grains (1 gram) 
of pancreatin and 20 grains (2 grams) of baking soda with 200 cc. of 
water. 



2. Take 10 cc. of artificial pancreatic juice in a test tube and to it 
add corn-starch paste. Set for two hours in a place where body tempera- 
tures can be maintained. Test for grape sugar. What is the effect of 
pancreatic juice on starch? What other juice has had a similar effect 
on starch? 

3. Take 10 cc. of artificial pancreatic juice to which you have added 
8 or 10 drops of olive oil or any other oil. Shake for a few minutes. What 
is the appearance of the mixture? When oil is so finely divided that 
the whole mixture looks milky it is called an emulsion. Is milk an 
emulsion? What fat or oil is suspended in the milk? Is milk a perfect 
emulsion in that it keeps the fat suspended indefinitely? What is 
cream? Does pancreatic juice make an emulsion? Does this 
aid digestion? 



132 HUMAN BIOLOGY 

4. What is the effect of pancreatic juice on fats and oils? 

5. It can also be shown that pancreatic juice breaks up fat into 
glycerine and fatty acids, and thus enables them to be absorbed into 

the system. 

6. Put in a test tube some minced white of egg with 10 cc. of pan- 
creatic juice. Keep the test tube at body temperature for two or three 
hours. Shake the solution from time to time to mix the solution. Test for 
peptone. What result? What other digestive juice digests minced 
white of egg? 

7. Note that the pancreatic juice has some starch, fat, and protein. 

8. How important would you judge the pancreatic juice to be? 

Action of Bile 

1. To a test tube containing minced white of egg add bile or gall. 
Put in a warm place for 3 or 4 hours. 

Note: Bile or gall may be obtained from the meat market by noti- 
fying the butcher a few days in advance of the time you need it. 

2. To a test tube containing corn-starch add bile and put in a warm 
place. 

3. To a test tube containing minced white of egg add bile and 
pancreatic juice and put in a warm place. 

4. To a test tube containing minced white of egg add pancreatic 
juice only. 

5. After a few hours compare the results when both bile and panel 
atic juice are added and where the pancreatic juice alone is added. 

6. Does bile alone digest the minced white of egg? Does bile alone 
digest corn-starch? What is the effect of bile on intestinal digestion? 



OSMOSIS 

1. Take an egg and break off the shell from the larger end without 
breaking the inside membrane. Have this area about an inch across. 

2. With a large needle make a hole in the small end of the egg op- 
posite. 

3. With sealing wax fasten a small glass tube about 8 inches long 
Dver the hole on the small end of the egg. 

4. Place the egg with large end down in a tumbler one quarter full 
of strong solution of grape sugar. " 

5. Observe after a few hours and after a few days. 

6. Do you observe anything rising in the glass tube? 

7. Break the egg and test the contents for grape sugar. With what 
result ? 

8. How could grape sugar get into the egg? 

9. Test the contents of the tumbler for protein. How could the 
protein get into the tumbler? 

10. Is it clear that grape sugar has passed into the egg and that protein 
has passed out of the egg? Is the membrane broken? 

11. This passing of solutions through animal or plant membrane is 
osmosis, and foods that have been digested or modified are taken up 
by the membranes of the digestive tract in the same way. 

133 



THE TEETH 

1. Obtain from a dentist the different types of teeth, such as in- 
cisors, cuspids, bicuspids, and molars. 

2. Examine an incisor. What is its shape? What is its adaptation? 

3. The crown is the part that shows in the mouth. The root is 
beneath the gum. The end of the nerve cavity shows at the lower part 
of the tooth. 

4. Sketch an incisor and label the above-mentioned features. 



5. Make similar studies of a cuspid, bicuspid, and molar. 

6. Note the special adaptation of each. 

7. From a microscopic slide or chart study a longitudinal section <>f 
a tooth. Note pulp cavity, dentine, enamel, and cement, ami maki 
sketch to show these features. 



8. Compare human teeth with those of the horse or cow or other 
lower animal and note the differences. 



l:M 



BONES 

1. From a butcher get long bones, irrregular bones, and, if possible, 
flat bones. 

2. Examine a long bone. Make out the shaft, the long part of the 
bone, the openings where the blood vessels enter, the rough places where 
muscles were attached. Sketch and label. 



3. Compare a flat bone with a long bone as to openings and rough 
places. 

4. Compare an irregular bone with that above. Do you find cor- 
responding features? 

5. Take a small bone and place in a weak solution of hydrochloric 
(muriatic) acid for a day or two. What has happened to the bone? 
What has been removed from the bone? Is animal or mineral matter 
left? 



6. Burn a small bone over an iron plate until it crumbles. What 
has been removed? Is animal or mineral matter left? 



7. Examine a microscopic slide or chart showing cross-section of a 
bone. Make out the following : a. large openings for blood vessels ; 
6. layers that encircle the opening ; c. small cavities separating the layers. 

8. Make a sketch to show these features. 



135 



. SKIN 

1. Examine the skin of your hand with a low-power lens. Make 
out the creases and ridges and small openings. 

2. Make a sketch to show the creases and ridges as you see them. 



3. Take your finger print on paper over which you have <\>\ 
printer's ink. Examine the loops and lines. Compare your finger prints 
with those of other pupils. How do they differ? What are finger 
prints? 

4. Make a study from a microscopic slide or chart of a CTOS —sect ion 
of the skin, and make out the following: a. epidermis \ b. dermis; 

c. hair follicle ; d. papilla; e. sebaceous glands ; /. perspiration glands. 

5. Make a sketch and label as many of these as you can make out. 



6. Put a few drops of ether or alcohol on your hand. What is the 
feeling due to the ether or alcohol? What causes this feeling? 

7. What is the effect of moderate evaporation on the skin 

8. What is the effect of rapid evaporation on the skin? 

L36 



NERVE TISSUE 

1. From a chart or microscopic slide study a nerve cell. 

2. Make out : 

a. Connective tissue 

b. Nerve sheath 

c. Axis cylinder 

d. Nucleus, etc. 

3. Sketch a nerve cell, and label as many as you can make out. 



4. Study a cross-section of the spinal cord from a chart or micro- 
scopic slide. 

5. Make out the following : 
• a. Ventral fissure 

b. Dorsal fissure 

c. The coverings. How many layers? 

d. White portion (under coverings) 

e. Gray portion (inside) 
/. Canal (in the center) 

Note : During life this canal carries the spinal fluid. 
g. Nerve roots 
h. Blood vessels 



137 



138 HUMAN BIOLOGY 

6. Sketch a cross-section and label as many of the features above as 
you can make out. 



7. Study spinal cells under a high-power lens or from a chart. 
Notice shape of the nuclei, axis-cylinder, etc. 

* ■ 

8. Sketch a spinal cell under high power and label as far as possible. 



THE EYE 

1. Examine your eye with a mirror. 

2. Make a sketch to show eyebrow, eyelid, cornea, iris, pupil, scle- 
rotic coat. The cornea is in front near iris and the outer part of the ball 
of the eye is part of the sclerotic coat. 



3. Examine your iris. What is the shape and color? Compare 
your eyes with the other pupils' as to shape and color. 

4. Examine the pupil of your eye. How is it formed? Does its 
shape change? Does its size change? 

5. Compare the pupil of your eye with the pupil of a cat's eye. How 
do they differ in size, shape, and varying form? 

6. From a model or chart make out the following : 
a. Sclerotic coat 

o. Choroid 

c. Retina 

d. Crystalline lens 

e. Iris 
/. Pupil 

g. Aqueous humor 
h. Vitreous humor 
i. Optic nerve 

7. Make a sketch to show features above and label. 



139 



THE EAR 

1. From a model or chart study the human ear. 

2. The external ear made up of the shell or passageway loading to 
the middle ear. 

3. The drum is at the middle of the passage. What is the function 
of the drum ? 

4. The middle ear is made up of three small bones. mall" 
stapes, and incus. It also contains the Eustachian tube leading to the 
throat. How could this Eustachian tube protect the drum from a 
jar or a big explosion ? 

5. The internal ear is made up of the vestibule, semicircular canals 
and the cochlea. 

6. Make a sketch to show the regions above and label. 



140 



THE CELL 

1. Examine a cell from some plant, from a prepared slide or chart. 

2. What is the shape ? Make out the following : 

a. The protoplasm region 

b. The nucleus 

c. The nucleolus 

d. The chromatin may be found in some specimens as deeply 
colored strands 

e. The cell wall is present in most specimens 

3. Make a sketch to show features above and label. 



4. Compare with plant cell above some animal cell as amoeba or 
Paramecium or other simple cell. 

5. Make a sketch and label as many regions as you can make out. 



6. Compare a prepared slide showing a human cell with a plant or 
lower animal cell. 



141 



142 HUMAN BIOLOGY 

7. What differences can you make out? 



8. What would you say in general of the plant cell, lower animal 
cell, and the cell from a human body, as to resemblances and 
differences ? 



